Merged with trunk (painfully)

git-svn-id: svn://localhost/ardour2/branches/midi@581 d708f5d6-7413-0410-9779-e7cbd77b26cf

69 files changed, 758 insertions, 628 deletions

diff --git a/libs/ardour/SConscript b/libs/ardour/SConscript
index 4f3fff3945..33e4633a79 100644
--- a/libs/ardour/SConscript
+++ b/libs/ardour/SConscript
@@ -58,7 +58,6 @@ ladspa_plugin.cc
 location.cc
 mtc_slave.cc
 named_selection.cc
-osc.cc
 panner.cc
 pcm_utils.cc
 playlist.cc
@@ -98,6 +97,7 @@ smpte.cc
 
 arch_specific_objects = [ ]
 
+osc_files = [ 'osc.cc' ]
 vst_files = [ 'vst_plugin.cc', 'session_vst.cc' ]
 coreaudio_files = [ 'coreaudio_source.cc' ]
 extra_sources = [ ]
@@ -105,6 +105,9 @@ extra_sources = [ ]
 if ardour['VST']:
 	extra_sources += vst_files
 
+if ardour['LIBLO']:
+    extra_sources += osc_files
+
 ardour.Append(CCFLAGS="-D_REENTRANT -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE")
 ardour.Append(CXXFLAGS="-DDATA_DIR=\\\""+final_prefix+"/share\\\"")
 ardour.Append(CXXFLAGS="-DMODULE_DIR=\\\""+final_prefix+"/lib\\\"")
@@ -173,7 +176,7 @@ if conf.CheckCHeader('sys/vfs.h'):
 if conf.CheckCHeader('/System/Library/Frameworks/CoreMIDI.framework/Headers/CoreMIDI.h'):
     ardour.Append(LINKFLAGS="-framework CoreMIDI")
 
-if conf.CheckCHeader('/System/Library/Frameworks/AudioToolbox.framework/Headers/ExtendedAudioFile.h'):
+if conf.CheckCHeader('/System/Library/Frameworks/AudioToolbox.framework/Headers/ExtendedAudioFile.h') and ardour['COREAUDIO'] == 1:
     ardour.Append(CXXFLAGS="-DHAVE_COREAUDIO")    
     ardour.Append(LINKFLAGS="-framework AudioToolbox")
     
@@ -199,9 +202,12 @@ ardour.Merge ([
 	     libraries['pbd3'],
 	     libraries['soundtouch'],
 	     libraries['midi++2'],
-	     libraries['lo'],
+             libraries['glib2'],
+             libraries['glibmm2']
 	     ])
 
+if ardour['LIBLO']:
+    ardour.Merge ([ libraries['lo'] ])
 
 ardour.VersionBuild(['version.cc', 'ardour/version.h'], 'SConscript')
 
diff --git a/libs/ardour/ardour/ardour.h b/libs/ardour/ardour/ardour.h
index 3308266f2f..fee6c601a2 100644
--- a/libs/ardour/ardour/ardour.h
+++ b/libs/ardour/ardour/ardour.h
@@ -26,14 +26,11 @@
 #include <signal.h>
 
 #include <pbd/error.h>
-#include <pbd/lockmonitor.h>
 #include <pbd/failed_constructor.h>
 
 #include <ardour/configuration.h>
 #include <ardour/types.h>
 
-using namespace PBD;
-
 namespace MIDI {
 	class MachineControl;
 	class Port;
diff --git a/libs/ardour/ardour/audioengine.h b/libs/ardour/ardour/audioengine.h
index 788ac679dd..50bf7dddcc 100644
--- a/libs/ardour/ardour/audioengine.h
+++ b/libs/ardour/ardour/audioengine.h
@@ -28,7 +28,9 @@
 #include <string>
 
 #include <sigc++/signal.h>
-#include <pthread.h>
+
+#include <glibmm/thread.h>
+
 #include <ardour/ardour.h>
 #include <jack/jack.h>
 #include <jack/transport.h>
@@ -59,7 +61,7 @@ class AudioEngine : public sigc::trackable
 	int start ();
 	bool running() const { return _running; }
 
-	PBD::NonBlockingLock& process_lock() { return _process_lock; }
+	Glib::Mutex& process_lock() { return _process_lock; }
 
 	jack_nframes_t frame_rate();
 	jack_nframes_t frames_per_cycle();
@@ -185,10 +187,10 @@ class AudioEngine : public sigc::trackable
 	ARDOUR::Session      *session;
 	jack_client_t       *_jack;
 	std::string           jack_client_name;
-	PBD::NonBlockingLock  port_lock;
-	PBD::NonBlockingLock _process_lock;
-	PBD::Lock             session_remove_lock;
-	pthread_cond_t        session_removed;
+	Glib::Mutex           port_lock;
+	Glib::Mutex           _process_lock;
+	Glib::Mutex           session_remove_lock;
+    Glib::Cond            session_removed;
 	bool                  session_remove_pending;
 	bool                 _running;
 	bool                 _has_run;
@@ -202,8 +204,6 @@ class AudioEngine : public sigc::trackable
 	sigc::slot<int,jack_nframes_t>  freewheel_action;
 	bool                  reconnect_on_halt;
 	int                  _usecs_per_cycle;
-	jack_nframes_t       last_meter_point;
-	jack_nframes_t       meter_interval;
 
 	typedef std::set<Port*> Ports;
 	Ports ports;
diff --git a/libs/ardour/ardour/audioregion.h b/libs/ardour/ardour/audioregion.h
index a146a20417..f210fa595b 100644
--- a/libs/ardour/ardour/audioregion.h
+++ b/libs/ardour/ardour/audioregion.h
@@ -75,10 +75,11 @@ class AudioRegion : public Region
 	AudioRegion (SourceList &, const XMLNode&);
 	~AudioRegion();
 
-	bool region_list_equivalent (const AudioRegion&);
-	bool source_equivalent (const AudioRegion&);
-	bool equivalent (const AudioRegion&);
-	bool size_equivalent (const AudioRegion&);
+	bool region_list_equivalent (const AudioRegion&) const ;
+	bool source_equivalent (const AudioRegion&) const;
+	bool equivalent (const AudioRegion&) const;
+	bool size_equivalent (const AudioRegion&) const;
+	bool overlap_equivalent (const AudioRegion&) const;
 
 	bool speed_mismatch (float) const;
 
diff --git a/libs/ardour/ardour/auditioner.h b/libs/ardour/ardour/auditioner.h
index a21ba94ac6..434ec32f97 100644
--- a/libs/ardour/ardour/auditioner.h
+++ b/libs/ardour/ardour/auditioner.h
@@ -22,10 +22,8 @@
 #define __ardour_auditioner_h__
 
 #include <string>
-#include <pthread.h>
 
-#include <pbd/lockmonitor.h>
-#include <pbd/atomic.h>
+#include <glibmm/thread.h>
 
 #include <ardour/ardour.h>
 #include <ardour/audio_track.h>
@@ -50,10 +48,10 @@ class Auditioner : public AudioTrack
 	int  play_audition (jack_nframes_t nframes);
 
 	void cancel_audition () { 
-		atomic_set (&_active, 0);
+		g_atomic_int_set (&_active, 0);
 	}
 
-	bool active() const { return atomic_read (&_active); }
+	bool active() const { return g_atomic_int_get (&_active); }
 
   private:
 	AudioRegion *the_region;
diff --git a/libs/ardour/ardour/automation_event.h b/libs/ardour/ardour/automation_event.h
index f26828a114..78daa531dd 100644
--- a/libs/ardour/ardour/automation_event.h
+++ b/libs/ardour/ardour/automation_event.h
@@ -26,7 +26,7 @@
 #include <cmath>
 
 #include <sigc++/signal.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/undo.h>
 #include <pbd/xml++.h>
 #include <ardour/ardour.h>
@@ -144,7 +144,7 @@ class AutomationList : public StateManager
 	std::pair<AutomationList::iterator,AutomationList::iterator> control_points_adjacent (double when);
 
 	template<class T> void apply_to_points (T& obj, void (T::*method)(const AutomationList&)) {
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		(obj.*method)(*this);
 	}
 
@@ -157,13 +157,13 @@ class AutomationList : public StateManager
 	double get_max_xval() const { return max_xval; }
 
 	double eval (double where) {
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		return unlocked_eval (where);
 	}
 
 	double rt_safe_eval (double where, bool& ok) {
 
-		TentativeLockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock, Glib::TRY_LOCK);
 
 		if ((ok = lm.locked())) {
 			return unlocked_eval (where);
@@ -186,7 +186,7 @@ class AutomationList : public StateManager
 	};
 
 	AutomationEventList events;
-	mutable PBD::NonBlockingLock lock;
+	mutable Glib::Mutex lock;
 	bool   _frozen;
 	bool    changed_when_thawed;
 	bool   _dirty;
diff --git a/libs/ardour/ardour/connection.h b/libs/ardour/ardour/connection.h
index b33af9cb21..899bffc06a 100644
--- a/libs/ardour/ardour/connection.h
+++ b/libs/ardour/ardour/connection.h
@@ -24,7 +24,7 @@
 #include <vector>
 #include <string>
 #include <sigc++/signal.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <ardour/stateful.h>
 
 using std::vector;
@@ -67,7 +67,7 @@ class Connection : public Stateful, public sigc::trackable {
 	Connection (const XMLNode&);
 
   private:
-	mutable PBD::Lock port_lock;
+	mutable Glib::Mutex port_lock;
 	vector<PortList> _ports;
 	string _name;
 	bool   _sysdep;
diff --git a/libs/ardour/ardour/control_protocol_manager.h b/libs/ardour/ardour/control_protocol_manager.h
index 42b5a69a48..03b21a299c 100644
--- a/libs/ardour/ardour/control_protocol_manager.h
+++ b/libs/ardour/ardour/control_protocol_manager.h
@@ -6,7 +6,7 @@
 
 #include <sigc++/sigc++.h>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 
 #include <ardour/stateful.h>
 
@@ -52,7 +52,7 @@ struct ControlProtocolInfo {
 	static ControlProtocolManager* _instance;
 
 	Session* _session;
-	PBD::Lock protocols_lock;
+	Glib::Mutex protocols_lock;
 	std::list<ControlProtocol*>    control_protocols;
 
 	void drop_session ();
diff --git a/libs/ardour/ardour/coreaudio_source.h b/libs/ardour/ardour/coreaudio_source.h
index 4193623006..736ea32df7 100644
--- a/libs/ardour/ardour/coreaudio_source.h
+++ b/libs/ardour/ardour/coreaudio_source.h
@@ -40,7 +40,7 @@ class CoreAudioSource : public ExternalSource {
 
 	mutable float *tmpbuf;
 	mutable jack_nframes_t tmpbufsize;
-	mutable PBD::Lock _tmpbuf_lock;
+	mutable Glib::Mutex _tmpbuf_lock;
 
 	void init (const string &str, bool build_peak);
 };
diff --git a/libs/ardour/ardour/curve.h b/libs/ardour/ardour/curve.h
index 1c6a4c5bc4..ede060e1cb 100644
--- a/libs/ardour/ardour/curve.h
+++ b/libs/ardour/ardour/curve.h
@@ -23,11 +23,10 @@
 
 #include <sys/types.h>
 #include <sigc++/signal.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/undo.h>
 #include <list>
 #include <algorithm>
-#include <pthread.h>
 #include <ardour/automation_event.h>
 
 namespace ARDOUR {
diff --git a/libs/ardour/ardour/diskstream.h b/libs/ardour/ardour/diskstream.h
index 9d2d336b02..316daba52f 100644
--- a/libs/ardour/ardour/diskstream.h
+++ b/libs/ardour/ardour/diskstream.h
@@ -33,7 +33,7 @@
 
 #include <pbd/fastlog.h>
 #include <pbd/ringbufferNPT.h>
-#include <pbd/atomic.h>
+ 
 
 #include <ardour/ardour.h>
 #include <ardour/configuration.h>
@@ -115,7 +115,7 @@ class DiskStream : public Stateful, public sigc::trackable
 	}
 
 	void set_record_enabled (bool yn, void *src);
-	bool record_enabled() const { return atomic_read (&_record_enabled); }
+	bool record_enabled() const { return g_atomic_int_get (&_record_enabled); }
 	void punch_in ();
 	void punch_out ();
 
@@ -365,7 +365,7 @@ class DiskStream : public Stateful, public sigc::trackable
 	AlignStyle               _persistent_alignment_style;
 	bool                      first_input_change;
 
-	PBD::NonBlockingLock  state_lock;
+	Glib::Mutex  state_lock;
 
 	jack_nframes_t scrub_start;
 	jack_nframes_t scrub_buffer_size;
@@ -404,7 +404,7 @@ class DiskStream : public Stateful, public sigc::trackable
 	};
 
 	vector<CaptureInfo*> capture_info;
-	PBD::Lock  capture_info_lock;
+	Glib::Mutex  capture_info_lock;
 	
 	void init (Flag);
 
diff --git a/libs/ardour/ardour/io.h b/libs/ardour/ardour/io.h
index 8321e9afda..c80a7abfaa 100644
--- a/libs/ardour/ardour/io.h
+++ b/libs/ardour/ardour/io.h
@@ -27,10 +27,11 @@
 #include <sigc++/signal.h>
 #include <jack/jack.h>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
+
 #include <pbd/fastlog.h>
 #include <pbd/undo.h>
-#include <pbd/atomic.h>
+
 #include <midi++/controllable.h>
 
 #include <ardour/ardour.h>
@@ -205,7 +206,15 @@ class IO : public Stateful, public ARDOUR::StateManager
 		}
 	}
 
-	static sigc::signal<void> Meter;
+    static void update_meters();
+
+private: 
+
+    static sigc::signal<void>   Meter;
+    static Glib::StaticMutex    m_meter_signal_lock;
+    sigc::connection            m_meter_connection;
+
+public:
 
 	/* automation */
 
@@ -261,7 +270,7 @@ class IO : public Stateful, public ARDOUR::StateManager
 	int ports_became_legal ();
 
   private:
-	mutable PBD::Lock io_lock;
+	mutable Glib::Mutex io_lock;
 
   protected:
 	Session&            _session;
@@ -269,7 +278,7 @@ class IO : public Stateful, public ARDOUR::StateManager
 	gain_t              _gain;
 	gain_t              _effective_gain;
 	gain_t              _desired_gain;
-	PBD::NonBlockingLock declick_lock;
+	Glib::Mutex         declick_lock;
 	vector<Port*>       _outputs;
 	vector<Port*>       _inputs;
 	vector<float>       _peak_power;
@@ -322,7 +331,7 @@ class IO : public Stateful, public ARDOUR::StateManager
 	jack_nframes_t last_automation_snapshot;
 	static jack_nframes_t _automation_interval;
 
-        AutoState      _gain_automation_state;
+    AutoState      _gain_automation_state;
 	AutoStyle      _gain_automation_style;
 
 	bool     apply_gain_automation;
@@ -331,7 +340,7 @@ class IO : public Stateful, public ARDOUR::StateManager
 	int  save_automation (const string&);
 	int  load_automation (const string&);
 	
-	PBD::NonBlockingLock automation_lock;
+	Glib::Mutex automation_lock;
 
 	/* AudioTrack::deprecated_use_diskstream_connections() needs these */
 
diff --git a/libs/ardour/ardour/location.h b/libs/ardour/ardour/location.h
index ee55adb600..75f4c5d12a 100644
--- a/libs/ardour/ardour/location.h
+++ b/libs/ardour/ardour/location.h
@@ -27,10 +27,10 @@
 #include <map>
 
 #include <sys/types.h>
-#include <pthread.h>
 #include <sigc++/signal.h>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
+
 #include <pbd/undo.h>
 
 #include "ardour.h"
@@ -159,18 +159,21 @@ class Locations : public Stateful, public StateManager
 	Location *first_location_before (jack_nframes_t);
 	Location *first_location_after (jack_nframes_t);
 
+	jack_nframes_t first_mark_before (jack_nframes_t);
+	jack_nframes_t first_mark_after (jack_nframes_t);
+
 	sigc::signal<void,Location*> current_changed;
 	sigc::signal<void>           changed;
 	sigc::signal<void,Location*> added;
 	sigc::signal<void,Location*> removed;
 
 	template<class T> void apply (T& obj, void (T::*method)(LocationList&)) {
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		(obj.*method)(locations);
 	}
 
 	template<class T1, class T2> void apply (T1& obj, void (T1::*method)(LocationList&, T2& arg), T2& arg) {
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		(obj.*method)(locations, arg);
 	}
 
@@ -187,7 +190,7 @@ class Locations : public Stateful, public StateManager
 
 	LocationList       locations;
 	Location          *current_location;
-	mutable PBD::Lock  lock;
+	mutable Glib::Mutex  lock;
 
 	int set_current_unlocked (Location *);
 	void location_changed (Location*);
diff --git a/libs/ardour/ardour/logcurve.h b/libs/ardour/ardour/logcurve.h
index 84911b0369..e65be55772 100644
--- a/libs/ardour/ardour/logcurve.h
+++ b/libs/ardour/ardour/logcurve.h
@@ -22,7 +22,7 @@
 #define __ardour_logcurve_h__
 
 #include <pbd/fastlog.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 
 namespace ARDOUR {
 
@@ -94,7 +94,7 @@ class LogCurve {
 	}
 	void set_length (uint32_t len) { l = len; }
 
-	mutable PBD::NonBlockingLock lock;
+	mutable Glib::Mutex lock;
 
   protected:
 	float a;
diff --git a/libs/ardour/ardour/playlist.h b/libs/ardour/ardour/playlist.h
index 78e3353084..d322f564ee 100644
--- a/libs/ardour/ardour/playlist.h
+++ b/libs/ardour/ardour/playlist.h
@@ -28,8 +28,9 @@
 
 #include <sys/stat.h>
 
+#include <glib.h>
+
 #include <sigc++/signal.h>
-#include <pbd/atomic.h>
 #include <pbd/undo.h>
 
 #include <ardour/ardour.h>
@@ -197,8 +198,8 @@ class Playlist : public Stateful, public StateManager {
 	void init (bool hide);
 
 	bool holding_state () const { 
-		return atomic_read (&block_notifications) != 0 ||
-			atomic_read (&ignore_state_changes) != 0;
+		return g_atomic_int_get (&block_notifications) != 0 ||
+			g_atomic_int_get (&ignore_state_changes) != 0;
 	}
 
 	/* prevent the compiler from ever generating these */
diff --git a/libs/ardour/ardour/redirect.h b/libs/ardour/ardour/redirect.h
index b370589079..ede55a1d80 100644
--- a/libs/ardour/ardour/redirect.h
+++ b/libs/ardour/ardour/redirect.h
@@ -27,7 +27,8 @@
 #include <map>
 #include <sigc++/signal.h>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
+
 #include <pbd/undo.h>
 
 #include <ardour/ardour.h>
@@ -131,7 +132,7 @@ class Redirect : public IO
 	map<uint32_t,AutomationList*> parameter_automation;
 	set<uint32_t> visible_parameter_automation;
 
-	mutable PBD::NonBlockingLock _automation_lock;
+	mutable Glib::Mutex _automation_lock;
 
 	void can_automate (uint32_t);
 	set<uint32_t> can_automate_list;
diff --git a/libs/ardour/ardour/region.h b/libs/ardour/ardour/region.h
index 5af5a660c1..3c94dad6fd 100644
--- a/libs/ardour/ardour/region.h
+++ b/libs/ardour/ardour/region.h
@@ -221,7 +221,7 @@ class Region : public Stateful, public StateManager
 	string                _name;        
 	mutable RegionEditState _first_edit;
 	int                   _frozen;
-	PBD::Lock              lock;
+	Glib::Mutex              lock;
 	ARDOUR::id_t          _id;
 	ARDOUR::Playlist*     _playlist;
 	mutable uint32_t      _read_data_count; // modified in read()
diff --git a/libs/ardour/ardour/route.h b/libs/ardour/ardour/route.h
index 8a707eb902..5699d9ef14 100644
--- a/libs/ardour/ardour/route.h
+++ b/libs/ardour/ardour/route.h
@@ -27,11 +27,8 @@
 #include <map>
 #include <string>
 
-#include <pthread.h>
-
-#include <pbd/atomic.h>
 #include <pbd/fastlog.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/xml++.h>
 #include <pbd/undo.h>
 #include <midi++/controllable.h>
@@ -142,14 +139,14 @@ class Route : public IO
 	void flush_redirects ();
 
 	template<class T> void foreach_redirect (T *obj, void (T::*func)(Redirect *)) {
-		RWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (redirect_lock);
 		for (RedirectList::iterator i = _redirects.begin(); i != _redirects.end(); ++i) {
 			(obj->*func) (*i);
 		}
 	}
 
 	Redirect *nth_redirect (uint32_t n) {
-		RWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (redirect_lock);
 		RedirectList::iterator i;
 		for (i = _redirects.begin(); i != _redirects.end() && n; ++i, --n);
 		if (i == _redirects.end()) {
@@ -294,9 +291,9 @@ class Route : public IO
 	jack_nframes_t           _roll_delay;
 	jack_nframes_t           _own_latency;
 	RedirectList             _redirects;
-	PBD::NonBlockingRWLock      redirect_lock;
+	Glib::RWLock      redirect_lock;
 	IO                      *_control_outs;
-	PBD::NonBlockingLock      control_outs_lock;
+	Glib::Mutex      control_outs_lock;
 	RouteGroup              *_edit_group;
 	RouteGroup              *_mix_group;
 	std::string              _comment;
diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index 923a5101fb..9339e448db 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -31,9 +31,9 @@
 
 #include <sndfile.h>
 
+#include <glibmm/thread.h>
+
 #include <pbd/error.h>
-#include <pbd/atomic.h>
-#include <pbd/lockmonitor.h>
 #include <pbd/undo.h>
 #include <pbd/pool.h>
 
@@ -47,6 +47,8 @@
 #include <ardour/gain.h>
 #include <ardour/io.h>
 
+#include <ardour/smpte.h>
+
 class XMLTree;
 class XMLNode;
 class AEffect;
@@ -274,7 +276,7 @@ class Session : public sigc::trackable, public Stateful
 	typedef list<DiskStream *> DiskStreamList;
 
 	Session::DiskStreamList disk_streams() const {
-		RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (diskstream_lock);
 		return diskstreams; /* XXX yes, force a copy */
 	}
 
@@ -284,7 +286,7 @@ class Session : public sigc::trackable, public Stateful
 	typedef list<Route *> RouteList;
 
 	RouteList get_routes() const {
-		RWLockMonitor rlock (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock rlock (route_lock);
 		return routes; /* XXX yes, force a copy */
 	}
 
@@ -310,7 +312,7 @@ class Session : public sigc::trackable, public Stateful
 	}
 
 	RecordState record_status() const {
-		return (RecordState) atomic_read (&_record_status);
+		return (RecordState) g_atomic_int_get (&_record_status);
 	}
 
 	bool actively_recording () {
@@ -1402,22 +1404,14 @@ class Session : public sigc::trackable, public Stateful
 	    static MultiAllocSingleReleasePool pool;
 	};
 
-<<<<<<< .working
+	mutable  gint   butler_active;
+	
 	//PBD::Lock       midi_lock;
 	//pthread_t       midi_thread;
 	//int             midi_request_pipe[2];
-	atomic_t        butler_active;
-	//RingBuffer<MIDIRequest*> midi_requests;
-/*
-=======
-	Glib::Mutex       midi_lock;
-	pthread_t       midi_thread;
-	int             midi_request_pipe[2];
-	mutable  gint   butler_active;
-	RingBuffer<MIDIRequest*> midi_requests;
 
->>>>>>> .merge-right.r579
-	int           start_midi_thread ();
+	//RingBuffer<MIDIRequest*> midi_requests;
+	/*int           start_midi_thread ();
 	void          terminate_midi_thread ();
 	void          poke_midi_thread ();
 	static void *_midi_thread_work (void *arg);
@@ -1465,7 +1459,7 @@ class Session : public sigc::trackable, public Stateful
 	/* disk-streams */
 
 	DiskStreamList  diskstreams; 
-	mutable PBD::NonBlockingRWLock diskstream_lock;
+	mutable Glib::RWLock diskstream_lock;
 	uint32_t dstream_buffer_size;
 	void add_diskstream (DiskStream*);
 	int  load_diskstreams (const XMLNode&);
@@ -1473,7 +1467,7 @@ class Session : public sigc::trackable, public Stateful
 	/* routes stuff */
 
 	RouteList       routes;
-	mutable PBD::NonBlockingRWLock route_lock;
+	mutable Glib::RWLock route_lock;
 	void   add_route (Route*);
 	uint32_t destructive_index;
 
@@ -1496,7 +1490,7 @@ class Session : public sigc::trackable, public Stateful
 
 	/* REGION MANAGEMENT */
 
-	mutable PBD::Lock region_lock;
+	mutable Glib::Mutex region_lock;
 	typedef map<ARDOUR::id_t,AudioRegion *> AudioRegionList;
 	AudioRegionList audio_regions;
 	
@@ -1509,7 +1503,7 @@ class Session : public sigc::trackable, public Stateful
 
 	/* SOURCES */
 	
-	mutable PBD::Lock source_lock;
+	mutable Glib::Mutex source_lock;
 	typedef std::map<id_t, Source *>    SourceList;
 
 	SourceList sources;
@@ -1523,7 +1517,7 @@ class Session : public sigc::trackable, public Stateful
 
 	/* PLAYLISTS */
 	
-	mutable PBD::Lock playlist_lock;
+	mutable Glib::Mutex playlist_lock;
 	typedef set<Playlist *> PlaylistList;
 	PlaylistList playlists;
 	PlaylistList unused_playlists;
@@ -1541,7 +1535,7 @@ class Session : public sigc::trackable, public Stateful
 
 	/* NAMED SELECTIONS */
 
-	mutable PBD::Lock named_selection_lock;
+	mutable Glib::Mutex named_selection_lock;
 	typedef set<NamedSelection *> NamedSelectionList;
 	NamedSelectionList named_selections;
 
@@ -1601,7 +1595,7 @@ class Session : public sigc::trackable, public Stateful
 	vector<space_and_path> session_dirs;
 	vector<space_and_path>::iterator last_rr_session_dir;
 	uint32_t _total_free_4k_blocks;
-	PBD::Lock space_lock;
+	Glib::Mutex space_lock;
 
 	static const char* sound_dir_name;
 	static const char* tape_dir_name;
@@ -1612,22 +1606,15 @@ class Session : public sigc::trackable, public Stateful
 	int ensure_sound_dir (string, string&);
 	void refresh_disk_space ();
 
-<<<<<<< .working
-	atomic_t _playback_load;
-	atomic_t _capture_load;
-	atomic_t _playback_load_min;
-	atomic_t _capture_load_min;
-=======
 	mutable gint _playback_load;
 	mutable gint _capture_load;
 	mutable gint _playback_load_min;
 	mutable gint _capture_load_min;
->>>>>>> .merge-right.r579
 
 	/* I/O Connections */
 
 	typedef list<Connection *> ConnectionList;
-	mutable PBD::Lock connection_lock;
+	mutable Glib::Mutex connection_lock;
 	ConnectionList _connections;
 	int load_connections (const XMLNode&);
 
@@ -1686,7 +1673,7 @@ class Session : public sigc::trackable, public Stateful
 	Sample*         click_emphasis_data;
 	jack_nframes_t  click_length;
 	jack_nframes_t  click_emphasis_length;
-	mutable PBD::NonBlockingRWLock click_lock;
+	mutable Glib::RWLock click_lock;
 
 	static const Sample         default_click[];
 	static const jack_nframes_t default_click_length;
diff --git a/libs/ardour/ardour/session_connection.h b/libs/ardour/ardour/session_connection.h
index caa20ed387..addc896b0b 100644
--- a/libs/ardour/ardour/session_connection.h
+++ b/libs/ardour/ardour/session_connection.h
@@ -29,7 +29,7 @@ namespace ARDOUR {
 template<class T> void 
 Session::foreach_connection (T *obj, void (T::*func)(Connection *)) 
 {
-	LockMonitor lm (connection_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (connection_lock);
 	for (ConnectionList::iterator i = _connections.begin(); i != _connections.end(); i++) {
 		(obj->*func) (*i);
 	}
diff --git a/libs/ardour/ardour/session_diskstream.h b/libs/ardour/ardour/session_diskstream.h
index 24693c5793..3c888c92c3 100644
--- a/libs/ardour/ardour/session_diskstream.h
+++ b/libs/ardour/ardour/session_diskstream.h
@@ -29,7 +29,7 @@ namespace ARDOUR {
 template<class T> void 
 Session::foreach_diskstream (T *obj, void (T::*func)(DiskStream&)) 
 {
-	RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (diskstream_lock);
 	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); i++) {
 		if (!(*i)->hidden()) {
 			(obj->*func) (**i);
diff --git a/libs/ardour/ardour/session_playlist.h b/libs/ardour/ardour/session_playlist.h
index 925a60182a..6f1b8dbd12 100644
--- a/libs/ardour/ardour/session_playlist.h
+++ b/libs/ardour/ardour/session_playlist.h
@@ -29,7 +29,7 @@ namespace ARDOUR {
 template<class T> void 
 Session::foreach_playlist (T *obj, void (T::*func)(Playlist *)) 
 {
-	LockMonitor lm (playlist_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (playlist_lock);
 	for (PlaylistList::iterator i = playlists.begin(); i != playlists.end(); i++) {
 		if (!(*i)->hidden()) {
 			(obj->*func) (*i);
diff --git a/libs/ardour/ardour/session_region.h b/libs/ardour/ardour/session_region.h
index 16580d8e73..13d88a9aa4 100644
--- a/libs/ardour/ardour/session_region.h
+++ b/libs/ardour/ardour/session_region.h
@@ -8,7 +8,7 @@ namespace ARDOUR {
 
 template<class T> void Session::foreach_audio_region (T *obj, void (T::*func)(AudioRegion *))
 {
-	LockMonitor lm (region_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (region_lock);
 	for (AudioRegionList::iterator i = audio_regions.begin(); i != audio_regions.end(); i++) {
 		(obj->*func) ((*i).second);
 	}
diff --git a/libs/ardour/ardour/session_route.h b/libs/ardour/ardour/session_route.h
index f3c8e3f5fb..afe78b394e 100644
--- a/libs/ardour/ardour/session_route.h
+++ b/libs/ardour/ardour/session_route.h
@@ -23,7 +23,8 @@
 
 #include <iostream>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
+
 #include <ardour/session.h>
 #include <ardour/route.h>
 
@@ -35,7 +36,7 @@ Session::foreach_route (T *obj, void (T::*func)(Route&))
 	RouteList public_order;
 
 	{
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		public_order = routes;
 	}
 
@@ -53,7 +54,7 @@ Session::foreach_route (T *obj, void (T::*func)(Route*))
 	RouteList public_order;
 
 	{
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		public_order = routes;
 	}
 
@@ -72,7 +73,7 @@ Session::foreach_route (T *obj, void (T::*func)(Route&, A), A arg1)
 	RouteList public_order;
 
 	{
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		public_order = routes;
 	}
 
diff --git a/libs/ardour/ardour/session_selection.h b/libs/ardour/ardour/session_selection.h
index a1dd31d7ff..a110c2c3da 100644
--- a/libs/ardour/ardour/session_selection.h
+++ b/libs/ardour/ardour/session_selection.h
@@ -29,7 +29,7 @@ namespace ARDOUR {
 template<class T> void 
 Session::foreach_named_selection (T& obj, void (T::*func)(NamedSelection&)) 
 {
-	LockMonitor lm (named_selection_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (named_selection_lock);
 	for (NamedSelectionList::iterator i = named_selections.begin(); i != named_selections.end(); i++) {
 		(obj.*func) (**i);
 	}
diff --git a/libs/ardour/ardour/slave.h b/libs/ardour/ardour/slave.h
index 90e63aed83..0079c10e0a 100644
--- a/libs/ardour/ardour/slave.h
+++ b/libs/ardour/ardour/slave.h
@@ -25,7 +25,6 @@
 
 #include <jack/jack.h>
 
-#include <pthread.h>
 #include <sigc++/signal.h>
 #include <ardour/ardour.h>
 #include <midi++/parser.h>
diff --git a/libs/ardour/ardour/sndfilesource.h b/libs/ardour/ardour/sndfilesource.h
index 2bd6042ec2..5d11c9ef09 100644
--- a/libs/ardour/ardour/sndfilesource.h
+++ b/libs/ardour/ardour/sndfilesource.h
@@ -43,7 +43,7 @@ class SndFileSource : public ExternalSource {
 
 	mutable float *tmpbuf;
 	mutable jack_nframes_t tmpbufsize;
-	mutable PBD::Lock _tmpbuf_lock;
+	mutable Glib::Mutex _tmpbuf_lock;
 
 	void init (const string &str, bool build_peak);
 };
diff --git a/libs/ardour/ardour/source.h b/libs/ardour/ardour/source.h
index 2eee7a7634..3781950fbf 100644
--- a/libs/ardour/ardour/source.h
+++ b/libs/ardour/ardour/source.h
@@ -25,10 +25,12 @@
 #include <vector>
 #include <string>
 
-#include <time.h>
+#include <ctime>
 
 #include <sigc++/signal.h>
 
+#include <glibmm/thread.h>
+
 #include <ardour/ardour.h>
 #include <ardour/stateful.h>
 #include <pbd/xml++.h>
@@ -125,7 +127,7 @@ class Source : public Stateful, public sigc::trackable
 	string            _name;
 	uint32_t     _use_cnt;
 	bool              _peaks_built;
-	mutable PBD::Lock _lock;
+	mutable Glib::Mutex _lock;
 	jack_nframes_t    _length;
 	bool               next_peak_clear_should_notify;
 	string             peakpath;
@@ -156,7 +158,7 @@ class Source : public Stateful, public sigc::trackable
 	};
 
 	static vector<Source*> pending_peak_sources;
-	static PBD::Lock pending_peak_sources_lock;
+	static Glib::StaticMutex pending_peak_sources_lock;
 
 	static void queue_for_peaks (Source&);
 	static void clear_queue_for_peaks ();
diff --git a/libs/ardour/ardour/tempo.h b/libs/ardour/ardour/tempo.h
index 2f04f603e7..13e8eb6348 100644
--- a/libs/ardour/ardour/tempo.h
+++ b/libs/ardour/ardour/tempo.h
@@ -25,8 +25,7 @@
 #include <string>
 #include <vector>
 #include <cmath>
-#include <pthread.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/undo.h>
 #include <sigc++/signal.h>
 
@@ -198,7 +197,7 @@ class TempoMap : public Stateful, public StateManager {
 	typedef vector<BBTPoint> BBTPointList;
 	
 	template<class T> void apply_with_metrics (T& obj, void (T::*method)(const Metrics&)) {
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		(obj.*method)(*metrics);
 	}
 
@@ -285,7 +284,7 @@ class TempoMap : public Stateful, public StateManager {
 	jack_nframes_t      last_bbt_when;
 	bool                last_bbt_valid;
 	BBT_Time            last_bbt;
-	mutable PBD::Lock   lock;
+	mutable Glib::Mutex   lock;
 	
 	void timestamp_metrics ();
 
diff --git a/libs/ardour/ardour/types.h b/libs/ardour/ardour/types.h
index 9cfe9d3a27..3d7ab4b59a 100644
--- a/libs/ardour/ardour/types.h
+++ b/libs/ardour/ardour/types.h
@@ -29,7 +29,6 @@
 
 #include <inttypes.h>
 #include <jack/types.h>
-#include <ardour/smpte.h>
 #include <map>
 
 #if __GNUC__ < 3
@@ -100,6 +99,33 @@ namespace ARDOUR {
 		Destructive
 	};
 
+	enum smpte_wrap_t {
+		smpte_wrap_none = 0,
+		smpte_wrap_frames,
+		smpte_wrap_seconds,
+		smpte_wrap_minutes,
+		smpte_wrap_hours
+	};
+
+	struct SMPTE_Time {
+		bool negative;
+		uint32_t hours;
+		uint32_t minutes;
+		uint32_t seconds;
+		uint32_t frames;
+		uint32_t subframes; // mostly not used
+
+		SMPTE_Time() {
+			negative = false;
+			hours = 0;
+			minutes = 0;
+			seconds = 0;
+			frames = 0;
+			subframes = 0;
+		}
+		
+	};
+
 	struct BBT_Time {
 	    uint32_t bars;
 	    uint32_t beats;
@@ -138,7 +164,7 @@ namespace ARDOUR {
 
 	    Type type;
 
-	    SMPTE::Time    smpte;
+	    SMPTE_Time     smpte;
 	    BBT_Time       bbt;
 
 	    union { 
diff --git a/libs/ardour/ardour/vst_plugin.h b/libs/ardour/ardour/vst_plugin.h
index 6ae64ab50c..ee8e6e986b 100644
--- a/libs/ardour/ardour/vst_plugin.h
+++ b/libs/ardour/ardour/vst_plugin.h
@@ -35,7 +35,6 @@
 #include <ardour/stateful.h>
 #include <ardour/plugin_state.h>
 #include <ardour/plugin.h>
-#include <ardour/vst_plugin.h>
 
 using std::string;
 using std::vector;
diff --git a/libs/ardour/audio_playlist.cc b/libs/ardour/audio_playlist.cc
index 53aa173ffd..9f3c02ce43 100644
--- a/libs/ardour/audio_playlist.cc
+++ b/libs/ardour/audio_playlist.cc
@@ -203,7 +203,7 @@ AudioPlaylist::read (Sample *buf, Sample *mixdown_buffer, float *gain_buffer, ch
 	   its OK to block (for short intervals).
 	*/
 
-	LockMonitor rm (region_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock rm (region_lock);
 
 	end =  start + cnt - 1;
 
@@ -504,7 +504,7 @@ AudioPlaylist::add_crossfade (Crossfade& xfade)
 	
 void AudioPlaylist::notify_crossfade_added (Crossfade *x)
 {
-	if (atomic_read(&block_notifications)) {
+	if (g_atomic_int_get(&block_notifications)) {
 		_pending_xfade_adds.insert (_pending_xfade_adds.end(), x);
 	} else {
 		NewCrossfade (x); /* EMIT SIGNAL */
@@ -886,8 +886,14 @@ AudioPlaylist::get_equivalent_regions (const AudioRegion& other, vector<AudioReg
 
 		AudioRegion* ar = dynamic_cast<AudioRegion*> (*i);
 
-		if (ar && ar->equivalent (other)) {
-			results.push_back (ar);
+		if (ar) {
+			if (Config->get_use_overlap_equivalency()) {
+				if (ar->overlap_equivalent (other)) {
+					results.push_back (ar);
+				} else if (ar->equivalent (other)) {
+					results.push_back (ar);
+				}
+			}
 		}
 	}
 }
diff --git a/libs/ardour/audio_track.cc b/libs/ardour/audio_track.cc
index 702d167a4f..30adc54d1a 100644
--- a/libs/ardour/audio_track.cc
+++ b/libs/ardour/audio_track.cc
@@ -625,7 +625,7 @@ AudioTrack::roll (jack_nframes_t nframes, jack_nframes_t start_frame, jack_nfram
 	jack_nframes_t transport_frame;
 
 	{
-		TentativeRWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (redirect_lock, Glib::TRY_LOCK);
 		if (lm.locked()) {
 			// automation snapshot can also be called from the non-rt context
 			// and it uses the redirect list, so we take the lock out here
@@ -709,7 +709,7 @@ AudioTrack::roll (jack_nframes_t nframes, jack_nframes_t start_frame, jack_nfram
 		/* don't waste time with automation if we're recording or we've just stopped (yes it can happen) */
 
 		if (!diskstream->record_enabled() && _session.transport_rolling()) {
-			TentativeLockMonitor am (automation_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock am (automation_lock, Glib::TRY_LOCK);
 			
 			if (am.locked() && gain_automation_playback()) {
 				apply_gain_automation = _gain_automation_curve.rt_safe_get_vector (start_frame, end_frame, _session.gain_automation_buffer(), nframes);
@@ -789,7 +789,7 @@ AudioTrack::export_stuff (vector<Sample*>& buffers, char * workbuf, uint32_t nbu
 	vector<Sample*>::iterator bi;
 	Sample * b;
 	
-	RWLockMonitor rlock (redirect_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock rlock (redirect_lock);
 		
 	if (diskstream->playlist()->read (buffers[0], mix_buffer, gain_buffer, workbuf, start, nframes) != nframes) {
 		return -1;
@@ -958,7 +958,7 @@ AudioTrack::freeze (InterThreadInfo& itt)
 	_freeze_record.have_mementos = true;
 
 	{
-		RWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (redirect_lock);
 		
 		for (RedirectList::iterator r = _redirects.begin(); r != _redirects.end(); ++r) {
 			
@@ -1015,7 +1015,7 @@ AudioTrack::unfreeze ()
 
 		} else {
 
-			RWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__); // should this be a write lock? jlc
+			Glib::RWLock::ReaderLock lm (redirect_lock); // should this be a write lock? jlc
 			for (RedirectList::iterator i = _redirects.begin(); i != _redirects.end(); ++i) {
 				for (vector<FreezeRecordInsertInfo*>::iterator ii = _freeze_record.insert_info.begin(); ii != _freeze_record.insert_info.end(); ++ii) {
 					if ((*ii)->id == (*i)->id()) {
diff --git a/libs/ardour/audioengine.cc b/libs/ardour/audioengine.cc
index a0cf29eb89..87866e7b31 100644
--- a/libs/ardour/audioengine.cc
+++ b/libs/ardour/audioengine.cc
@@ -22,6 +22,7 @@
 #include <cerrno>
 #include <vector>
 
+#include <glibmm/timer.h>
 #include <pbd/pthread_utils.h>
 
 #include <ardour/audioengine.h>
@@ -45,7 +46,6 @@ jack_nframes_t Port::long_over_length = 10;
 
 AudioEngine::AudioEngine (string client_name) 
 {
-	pthread_cond_init (&session_removed, 0);
 	session = 0;
 	session_remove_pending = false;
 	_running = false;
@@ -60,10 +60,12 @@ AudioEngine::AudioEngine (string client_name)
 	_buffer_size = 0;
 	_freewheeling = false;
 	_freewheel_thread_registered = false;
-	last_meter_point = 0;
-	meter_interval = 0;
-	meter_thread_id = (pthread_t) 0;
+    
+    m_meter_thread = 0;
+    m_meter_exit = false;
 
+    start_metering_thread();
+    
 	if (connect_to_jack (client_name)) {
 		throw NoBackendAvailable ();
 	}
@@ -76,9 +78,9 @@ AudioEngine::~AudioEngine ()
 		jack_client_close (_jack);
 	}
 
-	if (meter_thread_id != (pthread_t) 0) {
-		pthread_cancel (meter_thread_id);
-	}
+    if(m_meter_thread) {
+        g_atomic_int_inc(&m_meter_exit);
+    }
 }
 
 void
@@ -212,7 +214,6 @@ AudioEngine::_graph_order_callback (void *arg)
 	return 0;
 }
 
-/** @callgraph */
 int
 AudioEngine::_process_callback (jack_nframes_t nframes, void *arg)
 {
@@ -225,11 +226,10 @@ AudioEngine::_freewheel_callback (int onoff, void *arg)
 	static_cast<AudioEngine*>(arg)->_freewheeling = onoff;
 }
 
-/** @callgraph */
 int
 AudioEngine::process_callback (jack_nframes_t nframes)
 {
-	TentativeLockMonitor tm (_process_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock tm (_process_lock, Glib::TRY_LOCK);
 	jack_nframes_t next_processed_frames;
 
 	/* handle wrap around of total frames counter */
@@ -248,7 +248,7 @@ AudioEngine::process_callback (jack_nframes_t nframes)
 	if (session_remove_pending) {
 		session = 0;
 		session_remove_pending = false;
-		pthread_cond_signal (&session_removed);
+		session_removed.signal();
 		_processed_frames = next_processed_frames;
 		return 0;
 	}
@@ -271,14 +271,7 @@ AudioEngine::process_callback (jack_nframes_t nframes)
 		_processed_frames = next_processed_frames;
 		return 0;
 	}
-		
-	/* manage meters */
 
-	if ((meter_interval > _buffer_size) && (last_meter_point + meter_interval < next_processed_frames)) {
-		IO::Meter ();
-		last_meter_point = next_processed_frames;
-	}
-	
 	if (last_monitor_check + monitor_check_interval < next_processed_frames) {
 		for (Ports::iterator i = ports.begin(); i != ports.end(); ++i) {
 			
@@ -317,11 +310,6 @@ AudioEngine::jack_sample_rate_callback (jack_nframes_t nframes)
 	monitor_check_interval = nframes / 10;
 	last_monitor_check = 0;
 	
-	meter_interval = nframes / 100;
-	last_meter_point = 0;
-
-	maybe_start_metering_thread ();
-
 	if (session) {
 		session->set_frame_rate (nframes);
 	}
@@ -352,48 +340,25 @@ AudioEngine::jack_bufsize_callback (jack_nframes_t nframes)
 		session->set_block_size (_buffer_size);
 	}
 
-	maybe_start_metering_thread ();
-
 	return 0;
 }
 
 void
-AudioEngine::maybe_start_metering_thread ()
-{
-	if (meter_interval == 0) {
-		return;
-	}
-
-	if (_buffer_size == 0) {
-		return;
-	}
-
-	if (meter_interval < _buffer_size) {
-		if (meter_thread_id != (pthread_t) 0) {
-			pthread_cancel (meter_thread_id);
-		}
-		pthread_create (&meter_thread_id, 0, _meter_thread, this);
-	}
-}
-
-void*
-AudioEngine::_meter_thread (void *arg)
+AudioEngine::start_metering_thread ()
 {
-	return static_cast<AudioEngine*>(arg)->meter_thread ();
+    if(m_meter_thread == 0) {
+        m_meter_thread = Glib::Thread::create (sigc::mem_fun(this, &AudioEngine::meter_thread), false);
+    }
 }
 
-void*
+void
 AudioEngine::meter_thread ()
 {
-	PBD::ThreadCreated (pthread_self(), "Metering");
-
-	while (true) {
-		usleep (10000); /* 1/100th sec interval */
-		pthread_testcancel();
-		IO::Meter ();
+	while (g_atomic_int_get(&m_meter_exit) != true) {
+        Glib::usleep (10000); /* 1/100th sec interval */
+        IO::update_meters ();
 	}
-	
-	return 0;
+	return;
 }
 
 void 
@@ -407,13 +372,13 @@ AudioEngine::set_session (Session *s)
 void 
 AudioEngine::remove_session ()
 {
-	LockMonitor lm (_process_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_process_lock);
 
 	if (_running) {
 
 		if (session) {
 			session_remove_pending = true;
-			pthread_cond_wait (&session_removed, _process_lock.mutex());
+			session_removed.wait(_process_lock);
 		} 
 
 	} else {
@@ -450,7 +415,7 @@ AudioEngine::register_audio_input_port (const string& portname)
 
 	} else {
 
-		pthread_mutex_unlock (_process_lock.mutex());
+		_process_lock.unlock();
 		throw PortRegistrationFailure();
 	}
 
@@ -478,7 +443,7 @@ AudioEngine::register_audio_output_port (const string& portname)
 
 	} else {
 
-		pthread_mutex_unlock (_process_lock.mutex());
+		_process_lock.unlock();
 		throw PortRegistrationFailure ();
 	}
 
@@ -635,7 +600,7 @@ AudioEngine::frames_per_cycle ()
 Port *
 AudioEngine::get_port_by_name (const string& portname, bool keep)
 {
-	LockMonitor lm (_process_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_process_lock);
 
 	if (!_running) {
 		if (!_has_run) {
@@ -968,7 +933,7 @@ AudioEngine::reconnect_to_jack ()
 	if (_jack) {
 		disconnect_from_jack ();
 		/* XXX give jackd a chance */
-		usleep (250000);
+        Glib::usleep (250000);
 	}
 
 	if (connect_to_jack (jack_client_name)) {
diff --git a/libs/ardour/audioregion.cc b/libs/ardour/audioregion.cc
index 95201ab6f7..21773d9222 100644
--- a/libs/ardour/audioregion.cc
+++ b/libs/ardour/audioregion.cc
@@ -27,8 +27,9 @@
 #include <sigc++/bind.h>
 #include <sigc++/class_slot.h>
 
+#include <glibmm/thread.h>
+
 #include <pbd/basename.h>
-#include <pbd/lockmonitor.h>
 #include <pbd/xml++.h>
 
 #include <ardour/audioregion.h>
@@ -1139,15 +1140,15 @@ AudioRegion::master_source_names ()
 }
 
 bool
-AudioRegion::region_list_equivalent (const AudioRegion& other)
+AudioRegion::region_list_equivalent (const AudioRegion& other) const
 {
 	return size_equivalent (other) && source_equivalent (other) && _name == other._name;
 }
 
 bool
-AudioRegion::source_equivalent (const AudioRegion& other)
+AudioRegion::source_equivalent (const AudioRegion& other) const
 {
-	SourceList::iterator i;
+	SourceList::const_iterator i;
 	SourceList::const_iterator io;
 
 	for (i = sources.begin(), io = other.sources.begin(); i != sources.end() && io != other.sources.end(); ++i, ++io) {
@@ -1166,7 +1167,13 @@ AudioRegion::source_equivalent (const AudioRegion& other)
 }
 
 bool
-AudioRegion::equivalent (const AudioRegion& other)
+AudioRegion::overlap_equivalent (const AudioRegion& other) const
+{
+	return coverage (other.first_frame(), other.last_frame()) != OverlapNone;
+}
+
+bool
+AudioRegion::equivalent (const AudioRegion& other) const
 {
 	return _start == other._start &&
 		_position == other._position &&
@@ -1174,7 +1181,7 @@ AudioRegion::equivalent (const AudioRegion& other)
 }
 
 bool
-AudioRegion::size_equivalent (const AudioRegion& other)
+AudioRegion::size_equivalent (const AudioRegion& other) const
 {
 	return _start == other._start &&
 		_length == other._length;
diff --git a/libs/ardour/auditioner.cc b/libs/ardour/auditioner.cc
index ed97cf7b39..ce7b9a3e6f 100644
--- a/libs/ardour/auditioner.cc
+++ b/libs/ardour/auditioner.cc
@@ -18,7 +18,7 @@
     $Id$
 */
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 
 #include <ardour/diskstream.h>
 #include <ardour/audioregion.h>
@@ -57,7 +57,7 @@ Auditioner::Auditioner (Session& s)
 	IO::output_changed.connect (mem_fun (*this, &Auditioner::output_changed));
 
 	the_region = 0;
-	atomic_set (&_active, 0);
+	g_atomic_int_set (&_active, 0);
 }
 
 Auditioner::~Auditioner ()
@@ -74,14 +74,14 @@ Auditioner::prepare_playlist ()
 void
 Auditioner::audition_current_playlist ()
 {
-	if (atomic_read (&_active)) {
+	if (g_atomic_int_get (&_active)) {
 		/* don't go via session for this, because we are going
 		   to remain active.
 		*/
 		cancel_audition ();
 	}
 
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	diskstream->seek (0);
 	length = diskstream->playlist()->get_maximum_extent();
 	current_frame = 0;
@@ -90,20 +90,20 @@ Auditioner::audition_current_playlist ()
 
 	_panner->reset (n_outputs(), diskstream->n_channels());
 
-	atomic_set (&_active, 1);
+	g_atomic_int_set (&_active, 1);
 }
 
 void
 Auditioner::audition_region (AudioRegion& region)
 {
-	if (atomic_read (&_active)) {
+	if (g_atomic_int_get (&_active)) {
 		/* don't go via session for this, because we are going
 		   to remain active.
 		*/
 		cancel_audition ();
 	}
 
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 
 	the_region = new AudioRegion (region);
 	the_region->set_position (0, this);
@@ -126,7 +126,7 @@ Auditioner::audition_region (AudioRegion& region)
 	length = the_region->length();
 	diskstream->seek (0);
 	current_frame = 0;
-	atomic_set (&_active, 1);
+	g_atomic_int_set (&_active, 1);
 }
 
 int
@@ -136,7 +136,7 @@ Auditioner::play_audition (jack_nframes_t nframes)
 	jack_nframes_t this_nframes;
 	int ret;
 
-	if (atomic_read (&_active) == 0) {
+	if (g_atomic_int_get (&_active) == 0) {
 		silence (nframes, 0);
 		return 0;
 	}
diff --git a/libs/ardour/automation_event.cc b/libs/ardour/automation_event.cc
index 88932009bf..17888c4a7c 100644
--- a/libs/ardour/automation_event.cc
+++ b/libs/ardour/automation_event.cc
@@ -225,7 +225,7 @@ void
 AutomationList::clear ()
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		events.clear ();
 		if (!no_state) {
 			save_state (_("cleared"));
@@ -239,14 +239,14 @@ AutomationList::clear ()
 void
 AutomationList::x_scale (double factor)
 {
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	_x_scale (factor);
 }
 
 bool
 AutomationList::extend_to (double when)
 {
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	if (events.empty() || events.back()->when == when) {
 		return false;
 	}
@@ -285,7 +285,7 @@ AutomationList::rt_add (double when, double value)
 	// cerr << "RT: alist @ " << this << " add " << value << " @ " << when << endl;
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		iterator where;
 		TimeComparator cmp;
@@ -369,7 +369,7 @@ AutomationList::add (double when, double value, bool for_loading)
 	/* this is for graphical editing and loading data from storage */
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		TimeComparator cmp;
 		ControlEvent cp (when, 0.0f);
 		bool insert = true;
@@ -413,7 +413,7 @@ void
 AutomationList::erase (AutomationList::iterator i)
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		events.erase (i);
 		reposition_for_rt_add (0);
 		if (!no_state) {
@@ -428,7 +428,7 @@ void
 AutomationList::erase (AutomationList::iterator start, AutomationList::iterator end)
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		events.erase (start, end);
 		reposition_for_rt_add (0);
 		if (!no_state) {
@@ -445,7 +445,7 @@ AutomationList::reset_range (double start, double endt)
 	bool reset = false;
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+        Glib::Mutex::Lock lm (lock);
 		TimeComparator cmp;
 		ControlEvent cp (start, 0.0f);
 		iterator s;
@@ -481,7 +481,7 @@ AutomationList::erase_range (double start, double endt)
 	bool erased = false;
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		TimeComparator cmp;
 		ControlEvent cp (start, 0.0f);
 		iterator s;
@@ -515,7 +515,7 @@ AutomationList::move_range (iterator start, iterator end, double xdelta, double
 	*/
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		while (start != end) {
 			(*start)->when += xdelta;
@@ -542,7 +542,7 @@ AutomationList::modify (iterator iter, double when, double val)
 	*/
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		(*iter)->when = when;
 		(*iter)->value = val;
 		if (!no_state) {
@@ -558,7 +558,7 @@ AutomationList::modify (iterator iter, double when, double val)
 std::pair<AutomationList::iterator,AutomationList::iterator>
 AutomationList::control_points_adjacent (double xval)
 {
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	iterator i;
 	TimeComparator cmp;
 	ControlEvent cp (xval, 0.0f);
@@ -620,7 +620,7 @@ Change
 AutomationList::restore_state (StateManager::State& state) 
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		State* lstate = dynamic_cast<State*> (&state);
 
 		events.clear ();
@@ -655,7 +655,7 @@ void
 AutomationList::truncate_end (double last_coordinate)
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		ControlEvent cp (last_coordinate, 0);
 		list<ControlEvent*>::reverse_iterator i;
 		double last_val;
@@ -760,7 +760,7 @@ void
 AutomationList::truncate_start (double overall_length)
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		AutomationList::iterator i;
 		double first_legal_value;
 		double first_legal_coordinate;
@@ -998,7 +998,7 @@ AutomationList::cut (iterator start, iterator end)
 	AutomationList* nal = new AutomationList (default_value);
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		for (iterator x = start; x != end; ) {
 			iterator tmp;
@@ -1032,7 +1032,7 @@ AutomationList::cut_copy_clear (double start, double end, int op)
 	bool changed = false;
 	
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		if ((s = lower_bound (events.begin(), events.end(), &cp, cmp)) == events.end()) {
 			return nal;
@@ -1094,7 +1094,7 @@ AutomationList::copy (iterator start, iterator end)
 	AutomationList* nal = new AutomationList (default_value);
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		
 		for (iterator x = start; x != end; ) {
 			iterator tmp;
@@ -1141,7 +1141,7 @@ AutomationList::paste (AutomationList& alist, double pos, float times)
 	}
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		iterator where;
 		iterator prev;
 		double end = 0;
diff --git a/libs/ardour/connection.cc b/libs/ardour/connection.cc
index 83e0a87dc1..719751f7ba 100644
--- a/libs/ardour/connection.cc
+++ b/libs/ardour/connection.cc
@@ -28,7 +28,6 @@
 #include "i18n.h"
 
 using namespace ARDOUR;
-using namespace PBD;
 
 Connection::Connection (const XMLNode& node)
 {
@@ -58,7 +57,7 @@ void
 Connection::add_connection (int port, string portname)
 {
 	{
-		LockMonitor lm (port_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (port_lock);
 		_ports[port].push_back (portname);
 	}
 	 ConnectionsChanged (port); /* EMIT SIGNAL */
@@ -70,7 +69,7 @@ Connection::remove_connection (int port, string portname)
 	bool changed = false;
 
 	{
-		LockMonitor lm (port_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (port_lock);
 		PortList& pl = _ports[port];
 		PortList::iterator i = find (pl.begin(), pl.end(), portname);
 		
@@ -88,7 +87,7 @@ Connection::remove_connection (int port, string portname)
 const Connection::PortList&
 Connection::port_connections (int port) const
 {
-	LockMonitor lm (port_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (port_lock);
 	return _ports[port];
 }
 
@@ -102,7 +101,7 @@ void
 Connection::add_port ()
 {
 	{
-		LockMonitor lm (port_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (port_lock);
 		_ports.push_back (PortList());
 	}
 	 ConfigurationChanged(); /* EMIT SIGNAL */
@@ -114,7 +113,7 @@ Connection::remove_port (int which_port)
 	bool changed = false;
 
 	{
-		LockMonitor lm (port_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (port_lock);
 		vector<PortList>::iterator i;
 		int n;
 		
@@ -135,7 +134,7 @@ void
 Connection::clear ()
 {
 	{
-		LockMonitor lm (port_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (port_lock);
 		_ports.clear ();
 	}
 
diff --git a/libs/ardour/control_protocol_manager.cc b/libs/ardour/control_protocol_manager.cc
index ca1eefc3fe..57a89cc2d9 100644
--- a/libs/ardour/control_protocol_manager.cc
+++ b/libs/ardour/control_protocol_manager.cc
@@ -13,7 +13,6 @@
 
 
 using namespace ARDOUR;
-using namespace PBD;
 using namespace std;
 
 #include "i18n.h"
@@ -32,7 +31,7 @@ ControlProtocolManager::ControlProtocolManager ()
 
 ControlProtocolManager::~ControlProtocolManager()
 {
-	LockMonitor lm (protocols_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (protocols_lock);
 
 	for (list<ControlProtocol*>::iterator i = control_protocols.begin(); i != control_protocols.end(); ++i) {
 		delete (*i);
@@ -62,7 +61,7 @@ ControlProtocolManager::drop_session ()
 	_session = 0;
 
 	{
-		LockMonitor lm (protocols_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (protocols_lock);
 		for (list<ControlProtocol*>::iterator p = control_protocols.begin(); p != control_protocols.end(); ++p) {
 			delete *p;
 		}
@@ -89,7 +88,7 @@ ControlProtocolManager::instantiate (ControlProtocolInfo& cpi)
 		return 0;
 	}
 
-	LockMonitor lm (protocols_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (protocols_lock);
 	control_protocols.push_back (cpi.protocol);
 
 	return cpi.protocol;
@@ -113,7 +112,7 @@ ControlProtocolManager::teardown (ControlProtocolInfo& cpi)
 	cpi.descriptor->destroy (cpi.descriptor, cpi.protocol);
 	
 	{
-		LockMonitor lm (protocols_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (protocols_lock);
 		list<ControlProtocol*>::iterator p = find (control_protocols.begin(), control_protocols.end(), cpi.protocol);
 		if (p != control_protocols.end()) {
 			control_protocols.erase (p);
@@ -281,7 +280,7 @@ XMLNode&
 ControlProtocolManager::get_state (void)
 {
 	XMLNode* root = new XMLNode (state_node_name);
-	LockMonitor lm (protocols_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (protocols_lock);
 
 	for (list<ControlProtocolInfo*>::iterator i = control_protocol_info.begin(); i != control_protocol_info.end(); ++i) {
 		XMLNode* child = new XMLNode (X_("Protocol"));
diff --git a/libs/ardour/coreaudio_source.cc b/libs/ardour/coreaudio_source.cc
index d81630d6b7..67aaabfb88 100644
--- a/libs/ardour/coreaudio_source.cc
+++ b/libs/ardour/coreaudio_source.cc
@@ -66,29 +66,34 @@ CoreAudioSource::init (const string& idstr, bool build_peak)
 	}
 
 	/* note that we temporarily truncated _id at the colon */
-	FSRef ref;
-	err = FSPathMakeRef ((UInt8*)file.c_str(), &ref, 0);
+	FSRef fsr;
+	err = FSPathMakeRef ((UInt8*)file.c_str(), &fsr, 0);
 	if (err != noErr) {
+		cerr << "FSPathMakeRef " << err << endl;
 		throw failed_constructor();
 	}
 
-	err = ExtAudioFileOpen (&ref, &af);
+	err = ExtAudioFileOpen (&fsr, &af);
 	if (err != noErr) {
+		cerr << "ExtAudioFileOpen " << err << endl;
 		ExtAudioFileDispose (af);
 		throw failed_constructor();
 	}
 
 	AudioStreamBasicDescription file_asbd;
-	memset(&file_asbd, 0, sizeof(file_asbd));
-	size_t asbd_size = sizeof(file_asbd);
+	memset(&file_asbd, 0, sizeof(AudioStreamBasicDescription));
+	size_t asbd_size = sizeof(AudioStreamBasicDescription);
 	err = ExtAudioFileGetProperty(af,
 			kExtAudioFileProperty_FileDataFormat, &asbd_size, &file_asbd);
 	if (err != noErr) {
+		cerr << "ExtAudioFileGetProperty1 " << err << endl;
 		ExtAudioFileDispose (af);
 		throw failed_constructor();
 	}
 	n_channels = file_asbd.mChannelsPerFrame;
 
+	cerr << "number of channels: " << n_channels << endl;
+	
 	if (channel >= n_channels) {
 		error << string_compose(_("CoreAudioSource: file only contains %1 channels; %2 is invalid as a channel number"), n_channels, channel) << endmsg;
 		ExtAudioFileDispose (af);
@@ -96,42 +101,43 @@ CoreAudioSource::init (const string& idstr, bool build_peak)
 	}
 
 	int64_t ca_frames;
-	size_t prop_size = sizeof(ca_frames);
+	size_t prop_size = sizeof(int64_t);
 
 	err = ExtAudioFileGetProperty(af, kExtAudioFileProperty_FileLengthFrames, &prop_size, &ca_frames);
 	if (err != noErr) {
+		cerr << "ExtAudioFileGetProperty2 " << err << endl;
 		ExtAudioFileDispose (af);
 		throw failed_constructor();
 	}
-	_length = ca_frames;
 
+	_length = ca_frames;
 	_path = file;
 
-	if (build_peak) {
-		if (initialize_peakfile (false, file)) {
-			error << "initialize peakfile failed" << endmsg;
-			ExtAudioFileDispose (af);
-			throw failed_constructor ();
-		}
-	}
-	
 	AudioStreamBasicDescription client_asbd;
-	memset(&client_asbd, 0, sizeof(client_asbd));
+	memset(&client_asbd, 0, sizeof(AudioStreamBasicDescription));
+	client_asbd.mSampleRate = file_asbd.mSampleRate;
 	client_asbd.mFormatID = kAudioFormatLinearPCM;
 	client_asbd.mFormatFlags = kLinearPCMFormatFlagIsFloat;
-	client_asbd.mSampleRate = file_asbd.mSampleRate;
-
-	err = AudioFormatGetProperty(kAudioFormatProperty_FormatInfo, 0, NULL, &asbd_size, &client_asbd);
-	if (err != noErr) {
-		ExtAudioFileDispose (af);
-		throw failed_constructor ();
-	}
+	client_asbd.mBytesPerPacket = file_asbd.mChannelsPerFrame * 4;
+	client_asbd.mFramesPerPacket = 1;
+	client_asbd.mBytesPerFrame = client_asbd.mBytesPerPacket;
+	client_asbd.mChannelsPerFrame = file_asbd.mChannelsPerFrame;
+	client_asbd.mBitsPerChannel = 32;
 
 	err = ExtAudioFileSetProperty (af, kExtAudioFileProperty_ClientDataFormat, asbd_size, &client_asbd);
 	if (err != noErr) {
+		cerr << "ExtAudioFileSetProperty3 " << err << endl;
 		ExtAudioFileDispose (af);
 		throw failed_constructor ();
 	}
+	
+	if (build_peak) {
+		if (initialize_peakfile (false, file)) {
+			error << "initialize peakfile failed" << endmsg;
+			ExtAudioFileDispose (af);
+			throw failed_constructor ();
+		}
+	}
 }
 
 CoreAudioSource::~CoreAudioSource ()
@@ -173,7 +179,7 @@ CoreAudioSource::read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, ch
 	uint32_t real_cnt = cnt * n_channels;
 
 	{
-		LockMonitor lm (_tmpbuf_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (_tmpbuf_lock);
 		
 		if (tmpbufsize < real_cnt) {
 			
diff --git a/libs/ardour/curve.cc b/libs/ardour/curve.cc
index 613222020c..a515c3a39a 100644
--- a/libs/ardour/curve.cc
+++ b/libs/ardour/curve.cc
@@ -28,7 +28,7 @@
 #include <cfloat>
 #include <cmath>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <sigc++/bind.h>
 
 #include "ardour/curve.h"
@@ -37,7 +37,6 @@
 
 using namespace std;
 using namespace ARDOUR;
-using namespace PBD;
 using namespace sigc;
 
 Curve::Curve (double minv, double maxv, double canv, bool nostate)
@@ -204,7 +203,7 @@ Curve::solve ()
 bool
 Curve::rt_safe_get_vector (double x0, double x1, float *vec, int32_t veclen)
 {
-	TentativeLockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock, Glib::TRY_LOCK);
 
 	if (!lm.locked()) {
 		return false;
@@ -217,7 +216,7 @@ Curve::rt_safe_get_vector (double x0, double x1, float *vec, int32_t veclen)
 void
 Curve::get_vector (double x0, double x1, float *vec, int32_t veclen)
 {
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	_get_vector (x0, x1, vec, veclen);
 }
 
diff --git a/libs/ardour/destructive_filesource.cc b/libs/ardour/destructive_filesource.cc
index eaa1242f8c..9a4c2425e9 100644
--- a/libs/ardour/destructive_filesource.cc
+++ b/libs/ardour/destructive_filesource.cc
@@ -268,7 +268,7 @@ jack_nframes_t
 DestructiveFileSource::write (Sample* data, jack_nframes_t cnt, char * workbuf)
 {
 	{
-		LockMonitor lm (_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (_lock);
 		
 		jack_nframes_t old_file_pos;
 
diff --git a/libs/ardour/diskstream.cc b/libs/ardour/diskstream.cc
index 4fb13210fa..90e8387f3f 100644
--- a/libs/ardour/diskstream.cc
+++ b/libs/ardour/diskstream.cc
@@ -33,7 +33,7 @@
 
 #include <pbd/error.h>
 #include <pbd/basename.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/xml++.h>
 
 #include <ardour/ardour.h>
@@ -139,7 +139,7 @@ DiskStream::init (Flag f)
 	first_input_change = true;
 	_playlist = 0;
 	i_am_the_modifier = 0;
-	atomic_set (&_record_enabled, 0);
+	g_atomic_int_set (&_record_enabled, 0);
 	was_recording = false;
 	capture_start_frame = 0;
 	capture_captured = 0;
@@ -213,7 +213,7 @@ DiskStream::destroy_channel (ChannelInfo &chan)
 
 DiskStream::~DiskStream ()
 {
-	LockMonitor lm (state_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (state_lock);
 
 	if (_playlist) {
 		_playlist->unref ();
@@ -229,7 +229,7 @@ DiskStream::~DiskStream ()
 void
 DiskStream::handle_input_change (IOChange change, void *src)
 {
-	LockMonitor lm (state_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (state_lock);
 
 	if (!(input_change_pending & change)) {
 		input_change_pending = IOChange (input_change_pending|change);
@@ -241,7 +241,7 @@ void
 DiskStream::non_realtime_input_change ()
 {
 	{ 
-		LockMonitor lm (state_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (state_lock);
 
 		if (input_change_pending == NoChange) {
 			return;
@@ -349,7 +349,7 @@ int
 DiskStream::use_playlist (AudioPlaylist* playlist)
 {
 	{
-		LockMonitor lm (state_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (state_lock);
 
 		if (playlist == _playlist) {
 			return 0;
@@ -565,7 +565,7 @@ DiskStream::non_realtime_set_speed ()
 {
 	if (_buffer_reallocation_required)
 	{
-		LockMonitor lm (state_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (state_lock);
 		allocate_temporary_buffers ();
 
 		_buffer_reallocation_required = false;
@@ -753,7 +753,8 @@ DiskStream::process (jack_nframes_t transport_frame, jack_nframes_t nframes, jac
 	   returns a non-zero value, in which case, ::commit should not be called.
 	*/
 
-	if (pthread_mutex_trylock (state_lock.mutex())) {
+        // If we can't take the state lock return.
+	if (!state_lock.trylock()) {
 		return 1;
 	}
 
@@ -1002,7 +1003,7 @@ DiskStream::process (jack_nframes_t transport_frame, jack_nframes_t nframes, jac
 		   be called. unlock the state lock.
 		*/
 		
-		pthread_mutex_unlock (state_lock.mutex());
+		state_lock.unlock();
 	} 
 
 	return ret;
@@ -1011,7 +1012,7 @@ DiskStream::process (jack_nframes_t transport_frame, jack_nframes_t nframes, jac
 void
 DiskStream::recover ()
 {
-	pthread_mutex_unlock (state_lock.mutex());
+	state_lock.unlock();
 	_processed = false;
 }
 
@@ -1047,7 +1048,7 @@ DiskStream::commit (jack_nframes_t nframes)
 			|| channels[0].capture_buf->read_space() >= disk_io_chunk_frames;
 	}
 
-	pthread_mutex_unlock (state_lock.mutex());
+	state_lock.unlock();
 
 	_processed = false;
 
@@ -1140,7 +1141,7 @@ DiskStream::overwrite_existing_buffers ()
 int
 DiskStream::seek (jack_nframes_t frame, bool complete_refill)
 {
-	LockMonitor lm (state_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (state_lock);
 	uint32_t n;
 	int ret;
 	ChannelList::iterator chan;
@@ -1702,7 +1703,7 @@ DiskStream::transport_stopped (struct tm& when, time_t twhen, bool abort_capture
 	}
 
 	/* XXX is there anything we can do if err != 0 ? */
-	LockMonitor lm (capture_info_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (capture_info_lock);
 	
 	if (capture_info.empty()) {
 		return;
@@ -1925,7 +1926,7 @@ DiskStream::set_record_enabled (bool yn, void* src)
 
 	if (record_enabled() != yn) {
 		if (yn) {
-			atomic_set (&_record_enabled, 1);
+			g_atomic_int_set (&_record_enabled, 1);
 			capturing_sources.clear ();
 			if (Config->get_use_hardware_monitoring())  {
 				for (ChannelList::iterator chan = channels.begin(); chan != channels.end(); ++chan) {
@@ -1941,7 +1942,7 @@ DiskStream::set_record_enabled (bool yn, void* src)
 			}
 
 		} else {
-			atomic_set (&_record_enabled, 0);
+			g_atomic_int_set (&_record_enabled, 0);
 			if (Config->get_use_hardware_monitoring()) {
 				for (ChannelList::iterator chan = channels.begin(); chan != channels.end(); ++chan) {
 					if ((*chan).source) {
@@ -2415,7 +2416,7 @@ DiskStream::set_loop (Location *location)
 jack_nframes_t
 DiskStream::get_capture_start_frame (uint32_t n)
 {
-	LockMonitor lm (capture_info_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (capture_info_lock);
 
 	if (capture_info.size() > n) {
 		return capture_info[n]->start;
@@ -2428,7 +2429,7 @@ DiskStream::get_capture_start_frame (uint32_t n)
 jack_nframes_t
 DiskStream::get_captured_frames (uint32_t n)
 {
-	LockMonitor lm (capture_info_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (capture_info_lock);
 
 	if (capture_info.size() > n) {
 		return capture_info[n]->frames;
diff --git a/libs/ardour/filesource.cc b/libs/ardour/filesource.cc
index 568ce46bd1..63a9a3d014 100644
--- a/libs/ardour/filesource.cc
+++ b/libs/ardour/filesource.cc
@@ -53,10 +53,11 @@
 #include <vector>
 #include <cstdio> /* for rename(2) */
 
+#include <glibmm.h>
+
 #include <pbd/stl_delete.h>
-#include <pbd/basename.h>
-#include <pbd/dirname.h>
-#include <pbd/lockmonitor.h>
+
+#include <glibmm/thread.h>
 #include <pbd/pathscanner.h>
 
 #include <ardour/ardour.h>
@@ -351,7 +352,7 @@ FileSource::set_allow_remove_if_empty (bool yn)
 int
 FileSource::set_name (string newname, bool destructive)
 {
-	LockMonitor lm (_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_lock);
 	string oldpath = _path;
 	string newpath = Session::change_audio_path_by_name (oldpath, _name, newname, destructive);
 
@@ -365,7 +366,7 @@ FileSource::set_name (string newname, bool destructive)
 		return -1;
 	}
 
-	_name = basename (newpath);
+	_name = Glib::path_get_basename (newpath);
 	_path = newpath;
 
 	return rename_peakfile (peak_path (_path));
@@ -680,7 +681,7 @@ FileSource::compute_header_size ()
 int
 FileSource::update_header (jack_nframes_t when, struct tm& now, time_t tnow)
 {
-	LockMonitor lm (_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_lock);
 
 	if (is_bwf) {
 		/* random code is 9 digits */
@@ -1009,7 +1010,7 @@ FileSource::mark_for_remove ()
 jack_nframes_t
 FileSource::read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char * workbuf) const
 {
-	LockMonitor lm (_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_lock);
 	return read_unlocked (dst, start, cnt, workbuf);
 }
 
@@ -1055,7 +1056,7 @@ jack_nframes_t
 FileSource::write (Sample *data, jack_nframes_t cnt, char * workbuf)
 {
 	{
-		LockMonitor lm (_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (_lock);
 		
 		jack_nframes_t oldlen;
 		int32_t frame_pos = _length;
@@ -1287,7 +1288,7 @@ FileSource::is_empty (string path)
 void
 FileSource::mark_streaming_write_completed ()
 {
-	LockMonitor lm (_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_lock);
 
 	next_peak_clear_should_notify = true;
 
@@ -1313,13 +1314,15 @@ FileSource::move_to_trash (const string trash_dir_name)
 	   on whichever filesystem it was already on.
 	*/
 
-	newpath = PBD::dirname (_path);
-	newpath = PBD::dirname (newpath);
+        // XXX Portability
+
+	newpath = Glib::path_get_dirname (_path);
+	newpath = Glib::path_get_dirname (newpath);
 
 	newpath += '/';
 	newpath += trash_dir_name;
 	newpath += '/';
-	newpath += PBD::basename (_path);
+	newpath += Glib::path_get_basename (_path);
 
 	if (access (newpath.c_str(), F_OK) == 0) {
 
diff --git a/libs/ardour/gdither.cc b/libs/ardour/gdither.cc
index 3cdd7ee89e..ec6bfaa2ea 100644
--- a/libs/ardour/gdither.cc
+++ b/libs/ardour/gdither.cc
@@ -175,7 +175,7 @@ inline static void gdither_innner_loop(const GDitherType dt,
     const int clamp_l)
 {
     uint32_t pos, i;
-    u_int8_t *o8 = (u_int8_t*) y;
+    uint8_t *o8 = (uint8_t*) y;
     int16_t *o16 = (int16_t*) y;
     int32_t *o32 = (int32_t*) y;
     float tmp, r, ideal;
diff --git a/libs/ardour/globals.cc b/libs/ardour/globals.cc
index a618f17be5..762ee101f8 100644
--- a/libs/ardour/globals.cc
+++ b/libs/ardour/globals.cc
@@ -40,7 +40,6 @@
 #include <midi++/mmc.h>
 
 #include <ardour/ardour.h>
-#include <ardour/audioengine.h>
 #include <ardour/audio_library.h>
 #include <ardour/configuration.h>
 #include <ardour/plugin_manager.h>
@@ -48,7 +47,10 @@
 #include <ardour/utils.h>
 #include <ardour/session.h>
 #include <ardour/control_protocol_manager.h>
+
+#ifdef HAVE_LIBLO
 #include <ardour/osc.h>
+#endif
 
 #include <ardour/mix.h>
 
@@ -60,7 +62,10 @@
 
 ARDOUR::Configuration* ARDOUR::Config = 0;
 ARDOUR::AudioLibrary* ARDOUR::Library = 0;
+
+#ifdef HAVE_LIBLO
 ARDOUR::OSC* ARDOUR::osc = 0;
+#endif
 
 using namespace ARDOUR;
 using namespace std;
@@ -75,6 +80,7 @@ Change ARDOUR::PositionChanged = ARDOUR::new_change ();
 Change ARDOUR::NameChanged = ARDOUR::new_change ();
 Change ARDOUR::BoundsChanged = Change (0); // see init(), below
 
+#ifdef HAVE_LIBLO
 static int
 setup_osc ()
 {
@@ -90,9 +96,10 @@ setup_osc ()
 		return 0;
 	}
 }
+#endif
 
 static int 
-setup_midi (AudioEngine& engine)
+setup_midi ()
 {
 	std::map<string,Configuration::MidiPortDescriptor*>::iterator i;
 	int nports;
@@ -102,8 +109,6 @@ setup_midi (AudioEngine& engine)
 		return 0;
 	}
 
-	MIDI::Manager::instance()->set_api_data(engine.jack());
-
 	for (i = Config->midi_ports.begin(); i != Config->midi_ports.end(); ++i) {
 		Configuration::MidiPortDescriptor* port_descriptor;
 
@@ -115,9 +120,7 @@ setup_midi (AudioEngine& engine)
 					   port_descriptor->type);
 
 		if (request.status != MIDI::PortRequest::OK) {
-			error << string_compose(
-				_("MIDI port specifications for \"%1\" (%2, %3) are not understandable."),
-				port_descriptor->tag, port_descriptor->mode, port_descriptor->type) << endmsg;
+			error << string_compose(_("MIDI port specifications for \"%1\" are not understandable."), port_descriptor->tag) << endmsg;
 			continue;
 		}
 		
@@ -168,6 +171,7 @@ setup_midi (AudioEngine& engine)
 	if (default_mmc_port == 0) {
 		warning << string_compose (_("No MMC control (MIDI port \"%1\" not available)"), Config->get_mmc_port_name()) 
 			<< endmsg;
+		return 0;
 	} 
 
 	if (default_mtc_port == 0) {
@@ -198,13 +202,15 @@ ARDOUR::init (AudioEngine& engine, bool use_vst, bool try_optimization, void (*s
 
 	Config->set_use_vst (use_vst);
 
-	if (setup_midi (engine)) {
+	if (setup_midi ()) {
 		return -1;
 	}
-
+    
+#ifdef HAVE_LIBLO
 	if (setup_osc ()) {
 		return -1;
 	}
+#endif
 
 #ifdef VST_SUPPORT
 	if (Config->get_use_vst() && fst_init (sighandler)) {
@@ -327,10 +333,17 @@ ARDOUR::new_change ()
 	Change c;
 	static uint32_t change_bit = 1;
 
-	/* XXX catch out-of-range */
+	/* catch out-of-range */
+	if (!change_bit)
+	{
+		fatal << _("programming error: ")
+			<< "change_bit out of range in ARDOUR::new_change()"
+			<< endmsg;
+		/*NOTREACHED*/
+	}
 
 	c = Change (change_bit);
-	change_bit <<= 1;
+	change_bit <<= 1;	// if it shifts too far, change_bit == 0
 
 	return c;
 }
diff --git a/libs/ardour/import.cc b/libs/ardour/import.cc
index 69d5ee7b11..c13816e648 100644
--- a/libs/ardour/import.cc
+++ b/libs/ardour/import.cc
@@ -30,7 +30,10 @@
 #include <sndfile.h>
 #include <samplerate.h>
 
+#include <glibmm.h>
+
 #include <pbd/basename.h>
+
 #include <ardour/ardour.h>
 #include <ardour/session.h>
 #include <ardour/diskstream.h>
@@ -212,7 +215,7 @@ Session::import_audiofile (import_status& status)
 			sources.push_back(newfiles[n]);
 		}
 
-		AudioRegion *r = new AudioRegion (sources, 0, newfiles[0]->length(), region_name_from_path (PBD::basename(basepath)),
+		AudioRegion *r = new AudioRegion (sources, 0, newfiles[0]->length(), region_name_from_path (Glib::path_get_basename (basepath)),
 					0, AudioRegion::Flag (AudioRegion::DefaultFlags | AudioRegion::WholeFile));
 		
 		status.new_regions.push_back (r);
@@ -228,7 +231,7 @@ Session::import_audiofile (import_status& status)
 			   did not bother to create whole-file AudioRegions for them. Do it now.
 			*/
 		
-			AudioRegion *r = new AudioRegion (*newfiles[n], 0, newfiles[n]->length(), region_name_from_path (PBD::basename (newfiles[n]->name())),
+			AudioRegion *r = new AudioRegion (*newfiles[n], 0, newfiles[n]->length(), region_name_from_path (Glib::path_get_basename (newfiles[n]->name())),
 						0, AudioRegion::Flag (AudioRegion::DefaultFlags | AudioRegion::WholeFile | AudioRegion::Import));
 
 			status.new_regions.push_back (r);
@@ -285,7 +288,7 @@ Session::import_audiofile (import_status& status)
 string
 Session::build_tmp_convert_name(string infile)
 {
-	string tmp_name(_path + "/." + PBD::basename (infile.c_str()) + "XXXXXX");
+	string tmp_name(_path + "/." + Glib::path_get_basename (infile.c_str()) + "XXXXXX");
 	char* tmp = new char[tmp_name.length() + 1];
 	tmp_name.copy(tmp, string::npos);
 	tmp[tmp_name.length()] = 0;
diff --git a/libs/ardour/insert.cc b/libs/ardour/insert.cc
index 2c74bdc1c0..c3c3462016 100644
--- a/libs/ardour/insert.cc
+++ b/libs/ardour/insert.cc
@@ -76,7 +76,7 @@ PluginInsert::PluginInsert (Session& s, Plugin& plug, Placement placement)
 	save_state (_("initial state"));
 
 	{
-		LockMonitor em (_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em (_session.engine().process_lock());
 		IO::MoreOutputs (output_streams ());
 	}
 
@@ -97,7 +97,7 @@ PluginInsert::PluginInsert (Session& s, const XMLNode& node)
 	_plugins[0]->ParameterChanged.connect (mem_fun (*this, &PluginInsert::parameter_changed));
 
 	{
-		LockMonitor em (_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em (_session.engine().process_lock());
 		IO::MoreOutputs (output_streams());
 	}
 }
@@ -410,7 +410,7 @@ PluginInsert::automation_run (vector<Sample *>& bufs, uint32_t nbufs, jack_nfram
 	jack_nframes_t now = _session.transport_frame ();
 	jack_nframes_t end = now + nframes;
 
-	TentativeLockMonitor lm (_automation_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_automation_lock, Glib::TRY_LOCK);
 
 	if (!lm.locked()) {
 		connect_and_run (bufs, nbufs, nframes, offset, false);
diff --git a/libs/ardour/io.cc b/libs/ardour/io.cc
index b6ea1eee6e..fa30463bd4 100644
--- a/libs/ardour/io.cc
+++ b/libs/ardour/io.cc
@@ -25,7 +25,8 @@
 
 #include <sigc++/bind.h>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
+
 #include <pbd/xml++.h>
 
 #include <ardour/audioengine.h>
@@ -70,6 +71,8 @@ sigc::signal<int>                 IO::PannersLegal;
 sigc::signal<void,uint32_t>  IO::MoreOutputs;
 sigc::signal<int>                 IO::PortsCreated;
 
+Glib::StaticMutex       IO::m_meter_signal_lock = GLIBMM_STATIC_MUTEX_INIT;
+
 /* this is a default mapper of MIDI control values to a gain coefficient.
    others can be imagined. see IO::set_midi_to_gain_function().
 */
@@ -126,13 +129,20 @@ IO::IO (Session& s, string name,
 
 	_gain_automation_state = Off;
 	_gain_automation_style = Absolute;
-
-	Meter.connect (mem_fun (*this, &IO::meter));
+    
+    {
+        // IO::Meter is emitted from another thread so the
+        // Meter signal must be protected.
+        Glib::Mutex::Lock guard (m_meter_signal_lock);
+        m_meter_connection = Meter.connect (mem_fun (*this, &IO::meter));
+    }
 }
 
 IO::~IO ()
 {
-	LockMonitor lm (io_lock, __LINE__, __FILE__);
+
+    Glib::Mutex::Lock guard (m_meter_signal_lock);
+	Glib::Mutex::Lock lm (io_lock);
 	vector<Port *>::iterator i;
 
 	for (i = _inputs.begin(); i != _inputs.end(); ++i) {
@@ -142,6 +152,8 @@ IO::~IO ()
 	for (i = _outputs.begin(); i != _outputs.end(); ++i) {
 		_session.engine().unregister_port (*i);
 	}
+
+    m_meter_connection.disconnect();
 }
 
 void
@@ -380,7 +392,7 @@ IO::deliver_output (vector<Sample *>& bufs, uint32_t nbufs, jack_nframes_t nfram
 	gain_t pangain = _gain;
 	
 	{
-		TentativeLockMonitor dm (declick_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock dm (declick_lock, Glib::TRY_LOCK);
 		
 		if (dm.locked()) {
 			dg = _desired_gain;
@@ -427,7 +439,7 @@ IO::deliver_output_no_pan (vector<Sample *>& bufs, uint32_t nbufs, jack_nframes_
 		
 	} else {
 
-		TentativeLockMonitor dm (declick_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock dm (declick_lock, Glib::TRY_LOCK);
 		
 		if (dm.locked()) {
 			dg = _desired_gain;
@@ -568,10 +580,10 @@ IO::disconnect_input (Port* our_port, string other_port, void* src)
 	}
 
 	{ 
-		LockMonitor em (_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em (_session.engine().process_lock());
 		
 		{
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 			
 			/* check that our_port is really one of ours */
 			
@@ -604,10 +616,10 @@ IO::connect_input (Port* our_port, string other_port, void* src)
 	}
 
 	{
-		LockMonitor em(_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em(_session.engine().process_lock());
 		
 		{
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 			
 			/* check that our_port is really one of ours */
 			
@@ -638,10 +650,10 @@ IO::disconnect_output (Port* our_port, string other_port, void* src)
 	}
 
 	{
-		LockMonitor em(_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em(_session.engine().process_lock());
 		
 		{
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 			
 			if (find (_outputs.begin(), _outputs.end(), our_port) == _outputs.end()) {
 				return -1;
@@ -671,10 +683,10 @@ IO::connect_output (Port* our_port, string other_port, void* src)
 	}
 
 	{
-		LockMonitor em(_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em(_session.engine().process_lock());
 		
 		{
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 			
 			/* check that our_port is really one of ours */
 			
@@ -730,10 +742,10 @@ IO::remove_output_port (Port* port, void* src)
 	IOChange change (NoChange);
 
 	{
-		LockMonitor em(_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em(_session.engine().process_lock());
 		
 		{
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 			
 			if (_noutputs - 1 == (uint32_t) _output_minimum) {
 				/* sorry, you can't do this */
@@ -779,10 +791,10 @@ IO::add_output_port (string destination, void* src)
 	char buf[64];
 
 	{
-		LockMonitor em(_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em(_session.engine().process_lock());
 		
 		{ 
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 			
 			if (_output_maximum >= 0 && (int) _noutputs == _output_maximum) {
 				return -1;
@@ -830,10 +842,10 @@ IO::remove_input_port (Port* port, void* src)
 	IOChange change (NoChange);
 
 	{
-		LockMonitor em(_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em(_session.engine().process_lock());
 		
 		{
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 
 			if (((int)_ninputs - 1) < _input_minimum) {
 				/* sorry, you can't do this */
@@ -880,10 +892,10 @@ IO::add_input_port (string source, void* src)
 	char buf[64];
 
 	{
-		LockMonitor em (_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em (_session.engine().process_lock());
 		
 		{ 
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 			
 			if (_input_maximum >= 0 && (int) _ninputs == _input_maximum) {
 				return -1;
@@ -931,10 +943,10 @@ int
 IO::disconnect_inputs (void* src)
 {
 	{ 
-		LockMonitor em (_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em (_session.engine().process_lock());
 		
 		{
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 			
 			for (vector<Port *>::iterator i = _inputs.begin(); i != _inputs.end(); ++i) {
 				_session.engine().disconnect (*i);
@@ -951,10 +963,10 @@ int
 IO::disconnect_outputs (void* src)
 {
 	{
-		LockMonitor em (_session.engine().process_lock(), __LINE__, __FILE__);
+		Glib::Mutex::Lock em (_session.engine().process_lock());
 		
 		{
-			LockMonitor lm (io_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (io_lock);
 			
 			for (vector<Port *>::iterator i = _outputs.begin(); i != _outputs.end(); ++i) {
 				_session.engine().disconnect (*i);
@@ -1063,8 +1075,8 @@ IO::ensure_io (uint32_t nin, uint32_t nout, bool clear, void* src)
 	}
 
 	{
-		LockMonitor em (_session.engine().process_lock(), __LINE__, __FILE__);
-		LockMonitor lm (io_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock em (_session.engine().process_lock());
+		Glib::Mutex::Lock lm (io_lock);
 
 		Port* port;
 		
@@ -1212,8 +1224,8 @@ IO::ensure_inputs (uint32_t n, bool clear, bool lockit, void* src)
 	}
 	
 	if (lockit) {
-		LockMonitor em (_session.engine().process_lock(), __LINE__, __FILE__);
-		LockMonitor im (io_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock em (_session.engine().process_lock());
+		Glib::Mutex::Lock im (io_lock);
 		changed = ensure_inputs_locked (n, clear, src);
 	} else {
 		changed = ensure_inputs_locked (n, clear, src);
@@ -1314,8 +1326,8 @@ IO::ensure_outputs (uint32_t n, bool clear, bool lockit, void* src)
 	/* XXX caller should hold io_lock, but generally doesn't */
 
 	if (lockit) {
-		LockMonitor em (_session.engine().process_lock(), __LINE__, __FILE__);
-		LockMonitor im (io_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock em (_session.engine().process_lock());
+		Glib::Mutex::Lock im (io_lock);
 		changed = ensure_outputs_locked (n, clear, src);
 	} else {
 		changed = ensure_outputs_locked (n, clear, src);
@@ -1389,7 +1401,7 @@ IO::state (bool full_state)
 	bool need_ins = true;
 	bool need_outs = true;
 	LocaleGuard lg (X_("POSIX"));
-	LockMonitor lm (io_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (io_lock);
 
 	node->add_property("name", _name);
 	snprintf (buf, sizeof(buf), "%" PRIu64, id());
@@ -2058,7 +2070,7 @@ IO::set_output_maximum (int n)
 void
 IO::set_port_latency (jack_nframes_t nframes)
 {
-	LockMonitor lm (io_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (io_lock);
 
 	for (vector<Port *>::iterator i = _outputs.begin(); i != _outputs.end(); ++i) {
 		(*i)->set_latency (nframes);
@@ -2109,8 +2121,8 @@ IO::use_input_connection (Connection& c, void* src)
 	uint32_t limit;
 
 	{
-		LockMonitor lm (_session.engine().process_lock(), __LINE__, __FILE__);
-		LockMonitor lm2 (io_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (_session.engine().process_lock());
+		Glib::Mutex::Lock lm2 (io_lock);
 		
 		limit = c.nports();
 		
@@ -2187,8 +2199,8 @@ IO::use_output_connection (Connection& c, void* src)
 	uint32_t limit;	
 
 	{
-		LockMonitor lm (_session.engine().process_lock(), __LINE__, __FILE__);
-		LockMonitor lm2 (io_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (_session.engine().process_lock());
+		Glib::Mutex::Lock lm2 (io_lock);
 
 		limit = c.nports();
 			
@@ -2437,10 +2449,26 @@ IO::send_state_changed ()
 	return;
 }
 
+/**
+    Update the peak meters.
+
+    The meter signal lock is taken to prevent modification of the 
+    Meter signal while updating the meters, taking the meter signal
+    lock prior to taking the io_lock ensures that all IO will remain 
+    valid while metering.
+*/   
+void
+IO::update_meters()
+{
+    Glib::Mutex::Lock guard (m_meter_signal_lock);
+    
+    Meter();
+}
+
 void
 IO::meter ()
 {
-	LockMonitor lm (io_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (io_lock); // READER: meter thread.
 	uint32_t limit = max (_ninputs, _noutputs);
 	
 	for (uint32_t n = 0; n < limit; ++n) {
@@ -2602,7 +2630,7 @@ IO::load_automation (const string& path)
 void
 IO::clear_automation ()
 {
-	LockMonitor lm (automation_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (automation_lock);
 	_gain_automation_curve.clear ();
 	_panner->clear_automation ();
 }
@@ -2613,7 +2641,7 @@ IO::set_gain_automation_state (AutoState state)
 	bool changed = false;
 
 	{
-		LockMonitor lm (automation_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (automation_lock);
 
 		if (state != _gain_automation_curve.automation_state()) {
 			changed = true;
@@ -2638,7 +2666,7 @@ IO::set_gain_automation_style (AutoStyle style)
 	bool changed = false;
 
 	{
-		LockMonitor lm (automation_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (automation_lock);
 
 		if (style != _gain_automation_curve.automation_style()) {
 			changed = true;
@@ -2666,7 +2694,7 @@ IO::set_gain (gain_t val, void *src)
 	if (val>1.99526231f) val=1.99526231f;
 
 	{
-		LockMonitor dm (declick_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock dm (declick_lock);
 		_desired_gain = val;
 	}
 
diff --git a/libs/ardour/location.cc b/libs/ardour/location.cc
index 87a27e5c3d..28ec42a394 100644
--- a/libs/ardour/location.cc
+++ b/libs/ardour/location.cc
@@ -371,7 +371,7 @@ Locations::set_current (Location *loc, bool want_lock)
 	int ret;
 
 	if (want_lock) {
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		ret = set_current_unlocked (loc);
 	} else {
 		ret = set_current_unlocked (loc);
@@ -399,7 +399,7 @@ void
 Locations::clear ()
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		LocationList::iterator tmp;
 		for (LocationList::iterator i = locations.begin(); i != locations.end(); ) {
 			tmp = i;
@@ -424,7 +424,7 @@ void
 Locations::clear_markers ()
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		LocationList::iterator tmp;
 
 		for (LocationList::iterator i = locations.begin(); i != locations.end(); ) {
@@ -448,7 +448,7 @@ void
 Locations::clear_ranges ()
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		LocationList::iterator tmp;
 		
 		for (LocationList::iterator i = locations.begin(); i != locations.end(); ) {
@@ -477,7 +477,7 @@ void
 Locations::add (Location *loc, bool make_current)
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		locations.push_back (loc);
 
 		if (make_current) {
@@ -507,7 +507,7 @@ Locations::remove (Location *loc)
 	}
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		for (i = locations.begin(); i != locations.end(); ++i) {
 			if ((*i) == loc) {
@@ -547,7 +547,7 @@ Locations::get_state ()
 {
 	XMLNode *node = new XMLNode ("Locations");
 	LocationList::iterator iter;
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
        
 	for (iter  = locations.begin(); iter != locations.end(); ++iter) {
 		node->add_child_nocopy ((*iter)->get_state ());
@@ -570,7 +570,7 @@ Locations::set_state (const XMLNode& node)
 	nlist = node.children();
 	
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		for (niter = nlist.begin(); niter != nlist.end(); ++niter) {
 			Location *loc = new Location;
@@ -614,7 +614,7 @@ Locations::first_location_before (jack_nframes_t frame)
 	LocationList locs;
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		locs = locations;
 	}
 
@@ -638,7 +638,7 @@ Locations::first_location_after (jack_nframes_t frame)
 	LocationList locs;
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		locs = locations;
 	}
 
@@ -656,6 +656,80 @@ Locations::first_location_after (jack_nframes_t frame)
 	return 0;
 }
 
+jack_nframes_t
+Locations::first_mark_before (jack_nframes_t frame)
+{
+	LocationList locs;
+
+	{
+        Glib::Mutex::Lock lm (lock);
+		locs = locations;
+	}
+
+	LocationStartLaterComparison cmp;
+	locs.sort (cmp);
+
+	/* locs is now sorted latest..earliest */
+	
+	for (LocationList::iterator i = locs.begin(); i != locs.end(); ++i) {
+		if (!(*i)->is_hidden()) {
+			if ((*i)->is_mark()) {
+				/* MARK: start == end */
+				if ((*i)->start() < frame) {
+					return (*i)->start();
+				}
+			} else {
+				/* RANGE: start != end, compare start and end */
+				if ((*i)->end() < frame) {
+					return (*i)->end();
+				}
+				if ((*i)->start () < frame) {
+					return (*i)->start();
+				}
+			}
+		}
+	}
+
+	return 0;
+}
+
+jack_nframes_t
+Locations::first_mark_after (jack_nframes_t frame)
+{
+	LocationList locs;
+
+	{
+        Glib::Mutex::Lock lm (lock);
+		locs = locations;
+	}
+
+	LocationStartEarlierComparison cmp;
+	locs.sort (cmp);
+
+	/* locs is now sorted earliest..latest */
+	
+	for (LocationList::iterator i = locs.begin(); i != locs.end(); ++i) {
+		if (!(*i)->is_hidden()) {
+			if ((*i)->is_mark()) {
+				/* MARK, start == end so just compare start */
+				if ((*i)->start() > frame) {
+					return (*i)->start();
+				}
+			} else {
+				/* RANGE, start != end, compare start and end */
+				if ((*i)->start() > frame ) {
+					return (*i)->start ();
+				}
+				if ((*i)->end() > frame) {
+					return (*i)->end ();
+				}
+			}
+		}
+	}
+
+	return max_frames;
+}
+
 Location*
 Locations::end_location () const
 {
@@ -718,7 +792,7 @@ Change
 Locations::restore_state (StateManager::State& state) 
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		State* lstate = dynamic_cast<State*> (&state);
 
 		locations = lstate->locations;
@@ -743,7 +817,7 @@ uint32_t
 Locations::num_range_markers () const
 {
 	uint32_t cnt = 0;
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	for (LocationList::const_iterator i = locations.begin(); i != locations.end(); ++i) {
 		if ((*i)->is_range_marker()) {
 			++cnt;
diff --git a/libs/ardour/panner.cc b/libs/ardour/panner.cc
index 6b0013cada..bc7b472732 100644
--- a/libs/ardour/panner.cc
+++ b/libs/ardour/panner.cc
@@ -28,9 +28,10 @@
 #include <unistd.h>
 #include <float.h>
 
+#include <glibmm.h>
+
 #include <pbd/error.h>
 #include <pbd/failed_constructor.h>
-#include <pbd/basename.h>
 #include <pbd/xml++.h>
 
 #include <ardour/session.h>
@@ -1369,7 +1370,7 @@ Panner::state (bool full)
 
 	if (full) {
 		if (save () == 0) {
-			root->add_property (X_("automation"), PBD::basename (automation_path));
+			root->add_property (X_("automation"), Glib::path_get_basename (automation_path));
 		}
 	}
 
diff --git a/libs/ardour/playlist.cc b/libs/ardour/playlist.cc
index 73be1da86d..1bc6ccac6d 100644
--- a/libs/ardour/playlist.cc
+++ b/libs/ardour/playlist.cc
@@ -225,8 +225,8 @@ Playlist::copy_regions (RegionList& newlist) const
 void
 Playlist::init (bool hide)
 {
-	atomic_set (&block_notifications, 0);
-	atomic_set (&ignore_state_changes, 0);
+	g_atomic_int_set (&block_notifications, 0);
+	g_atomic_int_set (&ignore_state_changes, 0);
 	pending_modified = false;
 	pending_length = false;
 	_refcnt = 0;
@@ -292,13 +292,13 @@ void
 Playlist::freeze ()
 {
 	delay_notifications ();
-	atomic_inc (&ignore_state_changes);
+	g_atomic_int_inc (&ignore_state_changes);
 }
 
 void
 Playlist::thaw ()
 {
-	atomic_dec (&ignore_state_changes);
+	g_atomic_int_dec_and_test (&ignore_state_changes);
 	release_notifications ();
 }
 
@@ -306,14 +306,14 @@ Playlist::thaw ()
 void
 Playlist::delay_notifications ()
 {
-	atomic_inc (&block_notifications);
+	g_atomic_int_inc (&block_notifications);
 	freeze_length = _get_maximum_extent();
 }
 
 void
 Playlist::release_notifications ()
 {
-	if (atomic_dec_and_test(&block_notifications)) { 
+	if (g_atomic_int_dec_and_test (&block_notifications)) { 
 		flush_notifications ();
 	} 
 }
diff --git a/libs/ardour/redirect.cc b/libs/ardour/redirect.cc
index 403e6edddd..746d2790e2 100644
--- a/libs/ardour/redirect.cc
+++ b/libs/ardour/redirect.cc
@@ -126,7 +126,7 @@ Redirect::load_automation (string path)
 		return 1;
 	}
 
-	LockMonitor lm (_automation_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_automation_lock);
 	set<uint32_t> tosave;
 	parameter_automation.clear ();
 
@@ -159,7 +159,7 @@ Redirect::load_automation (string path)
 int
 Redirect::save_automation (string path)
 {
-	LockMonitor lm (_automation_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_automation_lock);
 	string fullpath;
 
 	if (parameter_automation.empty()) {
@@ -268,7 +268,7 @@ Redirect::state (bool full_state)
 void
 Redirect::what_has_automation (set<uint32_t>& s) const
 {
-	LockMonitor lm (_automation_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_automation_lock);
 	map<uint32_t,AutomationList*>::const_iterator li;
 	
 	for (li = parameter_automation.begin(); li != parameter_automation.end(); ++li) {
@@ -279,7 +279,7 @@ Redirect::what_has_automation (set<uint32_t>& s) const
 void
 Redirect::what_has_visible_automation (set<uint32_t>& s) const
 {
-	LockMonitor lm (_automation_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_automation_lock);
 	set<uint32_t>::const_iterator li;
 	
 	for (li = visible_parameter_automation.begin(); li != visible_parameter_automation.end(); ++li) {
diff --git a/libs/ardour/region.cc b/libs/ardour/region.cc
index 91d5704db2..08df23146b 100644
--- a/libs/ardour/region.cc
+++ b/libs/ardour/region.cc
@@ -26,7 +26,7 @@
 #include <sigc++/bind.h>
 #include <sigc++/class_slot.h>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/xml++.h>
 
 #include <ardour/region.h>
@@ -178,7 +178,7 @@ Region::restore_and_return_flags (RegionState& state)
 	Change what_changed = Change (0);
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		
 		if (_start != state._start) {
 			what_changed = Change (what_changed|StartChanged);	
@@ -947,7 +947,7 @@ Region::thaw (const string& why)
 	Change what_changed = Change (0);
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		if (_frozen && --_frozen > 0) {
 			return;
@@ -978,7 +978,7 @@ void
 Region::send_change (Change what_changed)
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		if (_frozen) {
 			pending_changed = Change (pending_changed|what_changed);
 			return;
diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc
index 2ce7f939b4..93fbb85e49 100644
--- a/libs/ardour/route.cc
+++ b/libs/ardour/route.cc
@@ -235,7 +235,7 @@ Route::process_output_buffers (vector<Sample*>& bufs, uint32_t nbufs,
 	declick = _pending_declick;
 
 	{
-		TentativeLockMonitor cm (control_outs_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock cm (control_outs_lock, Glib::TRY_LOCK);
 		
 		if (cm.locked()) {
 			co = _control_outs;
@@ -245,7 +245,7 @@ Route::process_output_buffers (vector<Sample*>& bufs, uint32_t nbufs,
 	}
 	
 	{ 
-		TentativeLockMonitor dm (declick_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock dm (declick_lock, Glib::TRY_LOCK);
 		
 		if (dm.locked()) {
 			dmg = desired_mute_gain;
@@ -330,7 +330,7 @@ Route::process_output_buffers (vector<Sample*>& bufs, uint32_t nbufs,
 	   -------------------------------------------------------------------------------------------------- */
 
 	if (with_redirects) {
-		TentativeRWLockMonitor rm (redirect_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock rm (redirect_lock, Glib::TRY_LOCK);
 		if (rm.locked()) {
 			if (mute_gain > 0 || !_mute_affects_pre_fader) {
 				for (i = _redirects.begin(); i != _redirects.end(); ++i) {
@@ -499,7 +499,7 @@ Route::process_output_buffers (vector<Sample*>& bufs, uint32_t nbufs,
 
 	if (post_fader_work) {
 
-		TentativeRWLockMonitor rm (redirect_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock rm (redirect_lock, Glib::TRY_LOCK);
 		if (rm.locked()) {
 			if (mute_gain > 0 || !_mute_affects_post_fader) {
 				for (i = _redirects.begin(); i != _redirects.end(); ++i) {
@@ -540,9 +540,6 @@ Route::process_output_buffers (vector<Sample*>& bufs, uint32_t nbufs,
 		solo_audible = solo_gain > 0;
 		mute_audible = dmg > 0 || !_mute_affects_control_outs;
 
-		cerr << _name << " have control outs, solo audible = " << solo_audible << " mute audible = " << mute_audible
-		     << endl;
-		
 		if ( // silent anyway
 
 			(_gain == 0 && !apply_gain_automation) || 
@@ -726,7 +723,7 @@ Route::set_solo (bool yn, void *src)
 void
 Route::set_solo_mute (bool yn)
 {
-	LockMonitor lm (declick_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (declick_lock);
 
 	/* Called by Session in response to another Route being soloed.
 	 */
@@ -760,7 +757,7 @@ Route::set_mute (bool yn, void *src)
 			_midi_mute_control.send_feedback (_muted);
 		}
 		
-		LockMonitor lm (declick_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (declick_lock);
 		desired_mute_gain = (yn?0.0f:1.0f);
 	}
 }
@@ -775,7 +772,7 @@ Route::add_redirect (Redirect *redirect, void *src, uint32_t* err_streams)
 	}
 
 	{
-		RWLockMonitor lm (redirect_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (redirect_lock);
 
 		PluginInsert* pi;
 		PortInsert* porti;
@@ -848,7 +845,7 @@ Route::add_redirects (const RedirectList& others, void *src, uint32_t* err_strea
 	}
 
 	{
-		RWLockMonitor lm (redirect_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (redirect_lock);
 
 		RedirectList::iterator existing_end = _redirects.end();
 		--existing_end;
@@ -907,7 +904,7 @@ Route::clear_redirects (void *src)
 	}
 
 	{
-		RWLockMonitor lm (redirect_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (redirect_lock);
 
 		for (RedirectList::iterator i = _redirects.begin(); i != _redirects.end(); ++i) {
 			delete *i;
@@ -937,7 +934,7 @@ Route::remove_redirect (Redirect *redirect, void *src, uint32_t* err_streams)
 	redirect_max_outs = 0;
 
 	{
-		RWLockMonitor lm (redirect_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (redirect_lock);
 		RedirectList::iterator i;
 		bool removed = false;
 
@@ -1016,7 +1013,7 @@ Route::remove_redirect (Redirect *redirect, void *src, uint32_t* err_streams)
 int
 Route::reset_plugin_counts (uint32_t* lpc)
 {
-	RWLockMonitor lm (redirect_lock, true, __LINE__, __FILE__);
+	Glib::RWLock::WriterLock lm (redirect_lock);
 	return _reset_plugin_counts (lpc);
 }
 
@@ -1186,7 +1183,7 @@ Route::copy_redirects (const Route& other, Placement placement, uint32_t* err_st
 	RedirectList to_be_deleted;
 
 	{
-		RWLockMonitor lm (redirect_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (redirect_lock);
 		RedirectList::iterator tmp;
 		RedirectList the_copy;
 
@@ -1265,7 +1262,7 @@ Route::copy_redirects (const Route& other, Placement placement, uint32_t* err_st
 void
 Route::all_redirects_flip ()
 {
-	RWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (redirect_lock);
 
 	if (_redirects.empty()) {
 		return;
@@ -1281,7 +1278,7 @@ Route::all_redirects_flip ()
 void
 Route::all_redirects_active (bool state)
 {
-	RWLockMonitor lm (redirect_lock, false,  __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (redirect_lock);
 
 	if (_redirects.empty()) {
 		return;
@@ -1303,7 +1300,7 @@ Route::sort_redirects (uint32_t* err_streams)
 {
 	{
 		RedirectSorter comparator;
-		RWLockMonitor lm (redirect_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (redirect_lock);
 		uint32_t old_rmo = redirect_max_outs;
 
 		/* the sweet power of C++ ... */
@@ -1782,7 +1779,7 @@ Route::silence (jack_nframes_t nframes, jack_nframes_t offset)
 		}
 
 		{ 
-			TentativeRWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+			Glib::RWLock::ReaderLock lm (redirect_lock, Glib::TRY_LOCK);
 			
 			if (lm.locked()) {
 				for (RedirectList::iterator i = _redirects.begin(); i != _redirects.end(); ++i) {
@@ -1807,7 +1804,7 @@ Route::silence (jack_nframes_t nframes, jack_nframes_t offset)
 int
 Route::set_control_outs (const vector<string>& ports)
 {
-	LockMonitor lm (control_outs_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (control_outs_lock);
 	vector<string>::const_iterator i;
 
  	if (_control_outs) {
@@ -2010,7 +2007,7 @@ Route::transport_stopped (bool abort_ignored, bool did_locate, bool can_flush_re
 	jack_nframes_t now = _session.transport_frame();
 
 	{
-		RWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (redirect_lock);
 
 		if (!did_locate) {
 			automation_snapshot (now);
@@ -2129,7 +2126,7 @@ Route::roll (jack_nframes_t nframes, jack_nframes_t start_frame, jack_nframes_t
 	     bool can_record, bool rec_monitors_input)
 {
 	{
-		TentativeRWLockMonitor lm(redirect_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (redirect_lock, Glib::TRY_LOCK);
 		if (lm.locked()) {
 			// automation snapshot can also be called from the non-rt context
 			// and it uses the redirect list, so we take the lock out here
@@ -2153,7 +2150,7 @@ Route::roll (jack_nframes_t nframes, jack_nframes_t start_frame, jack_nframes_t
 	apply_gain_automation = false;
 
 	{ 
-		TentativeLockMonitor am (automation_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock am (automation_lock, Glib::TRY_LOCK);
 		
 		if (am.locked() && _session.transport_rolling()) {
 			
@@ -2245,7 +2242,7 @@ Route::send_all_midi_feedback ()
 	if (_session.get_midi_feedback()) {
 
 		{
-			RWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+			Glib::RWLock::ReaderLock lm (redirect_lock);
 			for (RedirectList::iterator i = _redirects.begin(); i != _redirects.end(); ++i) {
 				(*i)->send_all_midi_feedback ();
 			}
@@ -2265,7 +2262,7 @@ Route::write_midi_feedback (MIDI::byte* buf, int32_t& bufsize)
 	buf = _midi_mute_control.write_feedback (buf, bufsize, _muted);
 
 	{
-		RWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (redirect_lock);
 		for (RedirectList::iterator i = _redirects.begin(); i != _redirects.end(); ++i) {
 			buf = (*i)->write_midi_feedback (buf, bufsize);
 		}
@@ -2281,7 +2278,7 @@ Route::flush_redirects ()
 	   this is called from the RT audio thread.
 	*/
 
-	RWLockMonitor lm (redirect_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (redirect_lock);
 
 	for (RedirectList::iterator i = _redirects.begin(); i != _redirects.end(); ++i) {
 		(*i)->deactivate ();
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 569060fe65..6c1dec8e81 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -32,12 +32,13 @@
 #include <sigc++/bind.h>
 #include <sigc++/retype.h>
 
+#include <glibmm.h>
+
 #include <pbd/error.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/pathscanner.h>
 #include <pbd/stl_delete.h>
 #include <pbd/basename.h>
-#include <pbd/dirname.h>
 
 #include <ardour/audioengine.h>
 #include <ardour/configuration.h>
@@ -64,7 +65,10 @@
 #include <ardour/crossfade.h>
 #include <ardour/playlist.h>
 #include <ardour/click.h>
+
+#ifdef HAVE_LIBLO
 #include <ardour/osc.h>
+#endif
 
 #include "i18n.h"
 
@@ -551,7 +555,7 @@ Session::set_worst_io_latencies (bool take_lock)
 	}
 
 	if (take_lock) {
-		route_lock.read_lock ();
+		route_lock.reader_lock ();
 	}
 	
 	for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
@@ -560,7 +564,7 @@ Session::set_worst_io_latencies (bool take_lock)
 	}
 
 	if (take_lock) {
-		route_lock.unlock ();
+		route_lock.reader_unlock ();
 	}
 }
 
@@ -795,9 +799,11 @@ Session::when_engine_running ()
 
 	_engine.set_session (this);
 
+#ifdef HAVE_LIBLO
 	/* and to OSC */
 
 	osc->set_session (*this);
+#endif
 
 	_state_of_the_state = Clean;
 
@@ -955,7 +961,7 @@ Session::set_auto_input (bool yn)
 			   a non-tentative rwlock here,  because the action must occur.
 			   The rarity and short potential lock duration makes this "OK"
 			*/
-			RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching to input = " << !auto_input << __FILE__ << __LINE__ << endl << endl;
@@ -973,7 +979,7 @@ void
 Session::reset_input_monitor_state ()
 {
 	if (transport_rolling()) {
-		RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if ((*i)->record_enabled ()) {
 				//cerr << "switching to input = " << !auto_input << __FILE__ << __LINE__ << endl << endl;
@@ -981,7 +987,7 @@ Session::reset_input_monitor_state ()
 			}
 		}
 	} else {
-		RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if ((*i)->record_enabled ()) {
 				//cerr << "switching to input = " << !auto_input << __FILE__ << __LINE__ << endl << endl;
@@ -1248,10 +1254,9 @@ void
 Session::enable_record ()
 {
 	/* XXX really atomic compare+swap here */
-	if (atomic_read (&_record_status) != Recording) {
-		atomic_set (&_record_status, Recording);
+	if (g_atomic_int_get (&_record_status) != Recording) {
+		g_atomic_int_set (&_record_status, Recording);
 		_last_record_location = _transport_frame;
-		// FIXME
 		//send_mmc_in_another_thread (MIDI::MachineControl::cmdRecordStrobe);
 
 		if (Config->get_use_hardware_monitoring() && auto_input) {
@@ -1259,7 +1264,7 @@ Session::enable_record ()
 			   a non-tentative rwlock here,  because the action must occur.
 			   The rarity and short potential lock duration makes this "OK"
 			*/
-			RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			
 			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
@@ -1277,17 +1282,16 @@ Session::disable_record (bool rt_context, bool force)
 {
 	RecordState rs;
 
-	if ((rs = (RecordState) atomic_read (&_record_status)) != Disabled) {
+	if ((rs = (RecordState) g_atomic_int_get (&_record_status)) != Disabled) {
 
 		if (!Config->get_latched_record_enable () || force) {
-			atomic_set (&_record_status, Disabled);
+			g_atomic_int_set (&_record_status, Disabled);
 		} else {
 			if (rs == Recording) {
-				atomic_set (&_record_status, Enabled);
+				g_atomic_int_set (&_record_status, Enabled);
 			}
 		}
 
-		// FIXME
 		//send_mmc_in_another_thread (MIDI::MachineControl::cmdRecordExit);
 
 		if (Config->get_use_hardware_monitoring() && auto_input) {
@@ -1295,7 +1299,7 @@ Session::disable_record (bool rt_context, bool force)
 			   a non-tentative rwlock here,  because the action must occur.
 			   The rarity and short potential lock duration makes this "OK"
 			*/
-			RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			
 			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
@@ -1315,14 +1319,14 @@ Session::disable_record (bool rt_context, bool force)
 void
 Session::step_back_from_record ()
 {
-	atomic_set (&_record_status, Enabled);
+	g_atomic_int_set (&_record_status, Enabled);
 
 	if (Config->get_use_hardware_monitoring()) {
 		/* Even though this can be called from RT context we are using
 		   a non-tentative rwlock here,  because the action must occur.
 		   The rarity and short potential lock duration makes this "OK"
 		*/
-		RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		
 		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		        if (auto_input && (*i)->record_enabled ()) {
@@ -1336,7 +1340,7 @@ Session::step_back_from_record ()
 void
 Session::maybe_enable_record ()
 {
-	atomic_set (&_record_status, Enabled);
+	g_atomic_int_set (&_record_status, Enabled);
 
 	/* XXX this save should really happen in another thread. its needed so that
 	   pending capture state can be recovered if we crash.
@@ -1445,8 +1449,8 @@ Session::set_block_size (jack_nframes_t nframes)
 	*/
 
 	{ 
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
-		RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
+		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		vector<Sample*>::iterator i;
 		uint32_t np;
 			
@@ -1523,7 +1527,7 @@ Session::set_default_fade (float steepness, float fade_msecs)
 
 	{
 		// jlc, WTF is this!
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		AudioRegion::set_default_fade (steepness, fade_frames);
 	}
 
@@ -1674,7 +1678,7 @@ Session::new_audio_track (int input_channels, int output_channels, TrackMode mod
 	/* count existing audio tracks */
 
 	{
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 			if (dynamic_cast<AudioTrack*>(*i) != 0) {
 				if (!(*i)->hidden()) {
@@ -1790,7 +1794,7 @@ Session::new_audio_route (int input_channels, int output_channels)
 	/* count existing audio busses */
 
 	{
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 			if (dynamic_cast<AudioTrack*>(*i) == 0) {
 				if (!(*i)->hidden()) {
@@ -1873,7 +1877,7 @@ void
 Session::add_route (Route* route)
 {
 	{ 
-		RWLockMonitor lm (route_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (route_lock);
 		routes.push_front (route);
 		resort_routes(0);
 	}
@@ -1904,7 +1908,7 @@ Session::add_diskstream (DiskStream* dstream)
 	dstream->do_refill(0, 0, 0);
 	
 	{ 
-		RWLockMonitor lm (diskstream_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (diskstream_lock);
 		diskstreams.push_back (dstream);
 	}
 
@@ -1932,7 +1936,7 @@ void
 Session::remove_route (Route& route)
 {
 	{ 	
-		RWLockMonitor lm (route_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (route_lock);
 		routes.remove (&route);
 		
 		/* deleting the master out seems like a dumb
@@ -1960,7 +1964,7 @@ Session::remove_route (Route& route)
 	}
 
 	{
-		RWLockMonitor lm (diskstream_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock lm (diskstream_lock);
 
 		AudioTrack* at;
 
@@ -1996,7 +2000,7 @@ Session::route_solo_changed (void* src, Route* route)
 		return;
 	}
 	
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
 	bool is_track;
 	
 	is_track = (dynamic_cast<AudioTrack*>(route) != 0);
@@ -2195,14 +2199,14 @@ Session::catch_up_on_solo ()
 	   basis, but needs the global overview that only the session
 	   has.
 	*/
-        RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+        Glib::RWLock::ReaderLock lm (route_lock);
 	update_route_solo_state();
 }	
 		
 Route *
 Session::route_by_name (string name)
 {
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
 
 	for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 		if ((*i)->name() == name) {
@@ -2216,7 +2220,7 @@ Session::route_by_name (string name)
 Route *
 Session::route_by_remote_id (uint32_t id)
 {
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
 
 	for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 		if ((*i)->remote_control_id() == id) {
@@ -2266,7 +2270,7 @@ Session::get_maximum_extent () const
 DiskStream *
 Session::diskstream_by_name (string name)
 {
-	RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
 	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if ((*i)->name() == name) {
@@ -2280,7 +2284,7 @@ Session::diskstream_by_name (string name)
 DiskStream *
 Session::diskstream_by_id (id_t id)
 {
-	RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
 	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if ((*i)->id() == id) {
@@ -2352,7 +2356,7 @@ Session::region_name (string& result, string base, bool newlevel) const
 
 	if (base == "") {
 		
-		LockMonitor lm (region_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (region_lock);
 
 		snprintf (buf, sizeof (buf), "%d", (int)audio_regions.size() + 1);
 
@@ -2380,7 +2384,7 @@ Session::region_name (string& result, string base, bool newlevel) const
 		bool name_taken = true;
 		
 		{
-			LockMonitor lm (region_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (region_lock);
 			
 			for (int n = 1; n < 5000; ++n) {
 				
@@ -2419,7 +2423,7 @@ Session::add_region (Region* region)
 	bool added = false;
 
 	{ 
-		LockMonitor lm (region_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (region_lock);
 
 		if ((ar = dynamic_cast<AudioRegion*> (region)) != 0) {
 
@@ -2496,7 +2500,7 @@ Session::remove_region (Region* region)
 	bool removed = false;
 
 	{ 
-		LockMonitor lm (region_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (region_lock);
 
 		if ((ar = dynamic_cast<AudioRegion*> (region)) != 0) {
 			if ((i = audio_regions.find (region->id())) != audio_regions.end()) {
@@ -2527,7 +2531,7 @@ Session::find_whole_file_parent (AudioRegion& child)
 {
 	AudioRegionList::iterator i;
 	AudioRegion* region;
-	LockMonitor lm (region_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (region_lock);
 
 	for (i = audio_regions.begin(); i != audio_regions.end(); ++i) {
 
@@ -2603,7 +2607,7 @@ Session::remove_last_capture ()
 {
 	list<Region*> r;
 
-	RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (diskstream_lock);
 	
 	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		list<Region*>& l = (*i)->last_capture_regions();
@@ -2633,7 +2637,7 @@ Session::add_source (Source* source)
 	pair<SourceList::key_type, SourceList::mapped_type> entry;
 
 	{
-		LockMonitor lm (source_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (source_lock);
 		entry.first = source->id();
 		entry.second = source;
 		sources.insert (entry);
@@ -2651,7 +2655,7 @@ Session::remove_source (Source* source)
 	SourceList::iterator i;
 
 	{ 
-		LockMonitor lm (source_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (source_lock);
 
 		if ((i = sources.find (source->id())) != sources.end()) {
 			sources.erase (i);
@@ -2673,7 +2677,7 @@ Session::remove_source (Source* source)
 Source *
 Session::get_source (ARDOUR::id_t id)
 {
-	LockMonitor lm (source_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (source_lock);
 	SourceList::iterator i;
 	Source* source = 0;
 
@@ -2691,8 +2695,8 @@ Session::peak_path_from_audio_path (string audio_path)
 
 	string res;
 
-	res = PBD::dirname (audio_path);
-	res = PBD::dirname (res);
+	res = Glib::path_get_dirname (audio_path);
+	res = Glib::path_get_dirname (res);
 	res += '/';
 	res += peak_dir_name;
 	res += '/';
@@ -2706,7 +2710,7 @@ string
 Session::change_audio_path_by_name (string path, string oldname, string newname, bool destructive)
 {
 	string look_for;
-	string old_basename = basename_nosuffix (oldname);
+	string old_basename = PBD::basename_nosuffix (oldname);
 	string new_legalized = legalize_for_path (newname);
 
 	/* note: we know (or assume) the old path is already valid */
@@ -2919,7 +2923,7 @@ Session::get_playlist (string name)
 Playlist *
 Session::playlist_by_name (string name)
 {
-	LockMonitor lm (playlist_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (playlist_lock);
 	for (PlaylistList::iterator i = playlists.begin(); i != playlists.end(); ++i) {
 		if ((*i)->name() == name) {
 			return* i;
@@ -2941,7 +2945,7 @@ Session::add_playlist (Playlist* playlist)
 	}
 
 	{ 
-		LockMonitor lm (playlist_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (playlist_lock);
 		if (find (playlists.begin(), playlists.end(), playlist) == playlists.end()) {
 			playlists.insert (playlists.begin(), playlist);
 			// playlist->ref();
@@ -2961,7 +2965,7 @@ Session::track_playlist (Playlist* pl, bool inuse)
 	PlaylistList::iterator x;
 
 	{ 
-		LockMonitor lm (playlist_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (playlist_lock);
 
 		if (!inuse) {
 			//cerr << "shifting playlist to unused: " << pl->name() << endl;
@@ -2993,7 +2997,7 @@ Session::remove_playlist (Playlist* playlist)
 	}
 
 	{ 
-		LockMonitor lm (playlist_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (playlist_lock);
 		// cerr << "removing playlist: " << playlist->name() << endl;
 
 		PlaylistList::iterator i;
@@ -3109,7 +3113,7 @@ void
 Session::set_all_solo (bool yn)
 {
 	{
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		
 		for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 			if (!(*i)->hidden()) {
@@ -3125,7 +3129,7 @@ void
 Session::set_all_mute (bool yn)
 {
 	{
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		
 		for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 			if (!(*i)->hidden()) {
@@ -3140,7 +3144,7 @@ Session::set_all_mute (bool yn)
 uint32_t
 Session::n_diskstreams () const
 {
-	RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (diskstream_lock);
 	uint32_t n = 0;
 
 	for (DiskStreamList::const_iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
@@ -3154,7 +3158,7 @@ Session::n_diskstreams () const
 void 
 Session::foreach_diskstream (void (DiskStream::*func)(void)) 
 {
-	RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (diskstream_lock);
 	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if (!(*i)->hidden()) {
 			((*i)->*func)();
@@ -3172,9 +3176,9 @@ Session::graph_reordered ()
 	if (_state_of_the_state & InitialConnecting) {
 		return;
 	}
-
-	RWLockMonitor lm1 (route_lock, true, __LINE__, __FILE__);
-	RWLockMonitor lm2 (diskstream_lock, false, __LINE__, __FILE__);
+	
+	Glib::RWLock::WriterLock lm1 (route_lock);
+	Glib::RWLock::ReaderLock lm2 (diskstream_lock);
 
 	resort_routes (0);
 
@@ -3202,7 +3206,7 @@ Session::record_enable_all ()
 void
 Session::record_enable_change_all (bool yn)
 {
-	RWLockMonitor lm1 (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm1 (route_lock);
 	
 	for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 		AudioTrack* at;
@@ -3287,7 +3291,7 @@ void
 Session::add_connection (ARDOUR::Connection* connection)
 {
 	{
-		LockMonitor (connection_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock guard (connection_lock);
 		_connections.push_back (connection);
 	}
 	
@@ -3302,7 +3306,7 @@ Session::remove_connection (ARDOUR::Connection* connection)
 	bool removed = false;
 
 	{
-		LockMonitor (connection_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock guard (connection_lock);
 		ConnectionList::iterator i = find (_connections.begin(), _connections.end(), connection);
 		
 		if (i != _connections.end()) {
@@ -3321,7 +3325,7 @@ Session::remove_connection (ARDOUR::Connection* connection)
 ARDOUR::Connection *
 Session::connection_by_name (string name) const
 {
-	LockMonitor lm (connection_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (connection_lock);
 
 	for (ConnectionList::const_iterator i = _connections.begin(); i != _connections.end(); ++i) {
 		if ((*i)->name() == name) {
@@ -3338,7 +3342,7 @@ Session::set_edit_mode (EditMode mode)
 	_edit_mode = mode;
 	
 	{ 
-		LockMonitor lm (playlist_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (playlist_lock);
 		
 		for (PlaylistList::iterator i = playlists.begin(); i != playlists.end(); ++i) {
 			(*i)->set_edit_mode (mode);
@@ -3413,7 +3417,7 @@ Session::next_insert_name ()
 NamedSelection *
 Session::named_selection_by_name (string name)
 {
-	LockMonitor lm (named_selection_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (named_selection_lock);
 	for (NamedSelectionList::iterator i = named_selections.begin(); i != named_selections.end(); ++i) {
 		if ((*i)->name == name) {
 			return* i;
@@ -3426,7 +3430,7 @@ void
 Session::add_named_selection (NamedSelection* named_selection)
 {
 	{ 
-		LockMonitor lm (named_selection_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (named_selection_lock);
 		named_selections.insert (named_selections.begin(), named_selection);
 	}
 
@@ -3441,7 +3445,7 @@ Session::remove_named_selection (NamedSelection* named_selection)
 	bool removed = false;
 
 	{ 
-		LockMonitor lm (named_selection_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (named_selection_lock);
 
 		NamedSelectionList::iterator i = find (named_selections.begin(), named_selections.end(), named_selection);
 
@@ -3463,7 +3467,7 @@ Session::reset_native_file_format ()
 {
 	// jlc - WHY take routelock?
 	//RWLockMonitor lm1 (route_lock, true, __LINE__, __FILE__);
-	RWLockMonitor lm2 (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm2 (diskstream_lock);
 
 	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		(*i)->reset_write_sources (false);
@@ -3473,7 +3477,7 @@ Session::reset_native_file_format ()
 bool
 Session::route_name_unique (string n) const
 {
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
 	
 	for (RouteList::const_iterator i = routes.begin(); i != routes.end(); ++i) {
 		if ((*i)->name() == n) {
@@ -3493,7 +3497,7 @@ Session::remove_file_source (FileSource& fs)
 uint32_t
 Session::n_playlists () const
 {
-	LockMonitor lm (playlist_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (playlist_lock);
 	return playlists.size();
 }
 
@@ -3542,7 +3546,7 @@ Session::add_instant_xml (XMLNode& node, const std::string& dir)
 int
 Session::freeze (InterThreadInfo& itt)
 {
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
 
 	for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 
@@ -3577,7 +3581,7 @@ Session::write_one_track (AudioTrack& track, jack_nframes_t start, jack_nframes_
 	char *  workbuf = 0;
 	const jack_nframes_t chunk_size = (256 * 1024)/4;
 
-	atomic_set (&processing_prohibited, 1);
+	g_atomic_int_set (&processing_prohibited, 1);
 	
 	/* call tree *MUST* hold route_lock */
 	
@@ -3698,7 +3702,7 @@ Session::write_one_track (AudioTrack& track, jack_nframes_t start, jack_nframes_
 		delete [] workbuf;
 	}
 	
-	atomic_set (&processing_prohibited, 0);
+	g_atomic_int_set (&processing_prohibited, 0);
 
 	itt.done = true;
 
@@ -3718,7 +3722,7 @@ uint32_t
 Session::ntracks () const
 {
 	uint32_t n = 0;
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
 
 	for (RouteList::const_iterator i = routes.begin(); i != routes.end(); ++i) {
 		if (dynamic_cast<AudioTrack*> (*i)) {
@@ -3733,7 +3737,7 @@ uint32_t
 Session::nbusses () const
 {
 	uint32_t n = 0;
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
 
 	for (RouteList::const_iterator i = routes.begin(); i != routes.end(); ++i) {
 		if (dynamic_cast<AudioTrack*> (*i) == 0) {
diff --git a/libs/ardour/session_butler.cc b/libs/ardour/session_butler.cc
index dafc28385b..ebe0d64548 100644
--- a/libs/ardour/session_butler.cc
+++ b/libs/ardour/session_butler.cc
@@ -26,8 +26,9 @@
 #include <fcntl.h>
 #include <poll.h>
 
+#include <glibmm/thread.h>
+
 #include <pbd/error.h>
-#include <pbd/lockmonitor.h>
 #include <pbd/pthread_utils.h>
 
 #include <ardour/configuration.h>
@@ -73,8 +74,6 @@ Session::start_butler_thread ()
 
 	Crossfade::set_buffer_size (dstream_buffer_size);
 
-	pthread_cond_init (&butler_paused, 0);
-	
 	butler_should_run = false;
 
 	if (pipe (butler_request_pipe)) {
@@ -114,7 +113,7 @@ Session::terminate_butler_thread ()
 void
 Session::schedule_butler_transport_work ()
 {
-	atomic_inc (&butler_should_do_transport_work);
+	g_atomic_int_inc (&butler_should_do_transport_work);
 	summon_butler ();
 }
 
@@ -135,19 +134,19 @@ Session::summon_butler ()
 void
 Session::stop_butler ()
 {
-	LockMonitor lm (butler_request_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (butler_request_lock);
 	char c = ButlerRequest::Pause;
 	::write (butler_request_pipe[1], &c, 1);
-	pthread_cond_wait (&butler_paused, butler_request_lock.mutex());
+	butler_paused.wait(butler_request_lock);
 }
 
 void
 Session::wait_till_butler_finished ()
 {
-	LockMonitor lm (butler_request_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (butler_request_lock);
 	char c = ButlerRequest::Wake;
 	::write (butler_request_pipe[1], &c, 1);
-	pthread_cond_wait (&butler_paused, butler_request_lock.mutex());
+	butler_paused.wait(butler_request_lock);
 }
 
 void *
@@ -158,7 +157,7 @@ Session::_butler_thread_work (void* arg)
 	return 0;
 }
 
-#define transport_work_requested() atomic_read(&butler_should_do_transport_work)
+#define transport_work_requested() g_atomic_int_get(&butler_should_do_transport_work)
 
 void *
 Session::butler_thread_work ()
@@ -256,7 +255,7 @@ Session::butler_thread_work ()
 
 		gettimeofday (&begin, 0);
 
-		RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock dsm (diskstream_lock);
 		
 		for (i = diskstreams.begin(); !transport_work_requested() && butler_should_run && i != diskstreams.end(); ++i) {
 			
@@ -355,7 +354,7 @@ Session::butler_thread_work ()
 
 
 		{
-			LockMonitor lm (butler_request_lock, __LINE__, __FILE__);
+			Glib::Mutex::Lock lm (butler_request_lock);
 
 			if (butler_should_run && (disk_work_outstanding || transport_work_requested())) {
 //				for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
@@ -365,7 +364,7 @@ Session::butler_thread_work ()
 				continue;
 			}
 
-			pthread_cond_signal (&butler_paused);
+			butler_paused.signal();
 		}
 	}
 
@@ -398,7 +397,7 @@ Session::overwrite_some_buffers (DiskStream* ds)
 
 	} else {
 
-		RWLockMonitor dm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock dm (diskstream_lock);
 		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			(*i)->set_pending_overwrite (true);
 		}
@@ -429,36 +428,36 @@ Session::write_data_rate () const
 uint32_t
 Session::playback_load ()
 {
-	return (uint32_t) atomic_read (&_playback_load);
+	return (uint32_t) g_atomic_int_get (&_playback_load);
 }
 
 uint32_t
 Session::capture_load ()
 {
-	return (uint32_t) atomic_read (&_capture_load);
+	return (uint32_t) g_atomic_int_get (&_capture_load);
 }
 
 uint32_t
 Session::playback_load_min ()
 {
-	return (uint32_t) atomic_read (&_playback_load_min);
+	return (uint32_t) g_atomic_int_get (&_playback_load_min);
 }
 
 uint32_t
 Session::capture_load_min ()
 {
-	return (uint32_t) atomic_read (&_capture_load_min);
+	return (uint32_t) g_atomic_int_get (&_capture_load_min);
 }
 
 void
 Session::reset_capture_load_min ()
 {
-	atomic_set (&_capture_load_min, 100);
+	g_atomic_int_set (&_capture_load_min, 100);
 }
 
 
 void
 Session::reset_playback_load_min ()
 {
-	atomic_set (&_playback_load_min, 100);
+	g_atomic_int_set (&_playback_load_min, 100);
 }
diff --git a/libs/ardour/session_click.cc b/libs/ardour/session_click.cc
index c9777500a2..4503287da1 100644
--- a/libs/ardour/session_click.cc
+++ b/libs/ardour/session_click.cc
@@ -47,7 +47,7 @@ Session::click (jack_nframes_t start, jack_nframes_t nframes, jack_nframes_t off
 		return;
 	}
 
-	TentativeRWLockMonitor clickm (click_lock, true, __LINE__, __FILE__);
+	Glib::RWLock::WriterLock clickm (click_lock, Glib::TRY_LOCK);
 	
 	if (!clickm.locked() || _transport_speed != 1.0 || !_clicking || click_data == 0) {
 		_click_io->silence (nframes, offset);
@@ -209,7 +209,7 @@ Session::setup_click_sounds (int which)
 void
 Session::clear_clicks ()
 {
-	RWLockMonitor lm (click_lock, true, __LINE__, __FILE__);
+	Glib::RWLock::WriterLock lm (click_lock);
 
 	for (Clicks::iterator i = clicks.begin(); i != clicks.end(); ++i) {
 		delete *i;
diff --git a/libs/ardour/session_events.cc b/libs/ardour/session_events.cc
index 7e0b6fbef5..c9b4339686 100644
--- a/libs/ardour/session_events.cc
+++ b/libs/ardour/session_events.cc
@@ -24,7 +24,7 @@
 #include <ardour/timestamps.h>
 
 #include <pbd/error.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 
 #include <ardour/ardour.h>
 #include <ardour/session.h>
diff --git a/libs/ardour/session_export.cc b/libs/ardour/session_export.cc
index 677b2c1258..183b6df237 100644
--- a/libs/ardour/session_export.cc
+++ b/libs/ardour/session_export.cc
@@ -37,7 +37,7 @@
 #include <sigc++/bind.h>
 
 #include <pbd/error.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 
 #include <ardour/gdither.h>
 #include <ardour/timestamps.h>
@@ -485,7 +485,7 @@ Session::prepare_to_export (AudioExportSpecification& spec)
 	/* take everyone out of awrite to avoid disasters */
 
 	{
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 			(*i)->protect_automation ();
 		}
@@ -494,7 +494,7 @@ Session::prepare_to_export (AudioExportSpecification& spec)
 	/* get everyone to the right position */
 
 	{
-		RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (diskstream_lock);
 		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if ((*i)-> seek (spec.start_frame, true)) {
 				error << string_compose (_("%1: cannot seek to %2 for export"),
@@ -524,7 +524,7 @@ Session::prepare_to_export (AudioExportSpecification& spec)
 
 	set_transport_speed (1.0, false);
 	butler_transport_work ();
-	atomic_set (&butler_should_do_transport_work, 0);
+	g_atomic_int_set (&butler_should_do_transport_work, 0);
 	post_transport ();
 
 	/* we are ready to go ... */
diff --git a/libs/ardour/session_feedback.cc b/libs/ardour/session_feedback.cc
index 600567892e..ea8580b3c2 100644
--- a/libs/ardour/session_feedback.cc
+++ b/libs/ardour/session_feedback.cc
@@ -28,8 +28,10 @@
 #include <midi++/types.h>
 #include <midi++/port.h>
 #include <midi++/manager.h>
+
+#include <glibmm/thread.h>
+
 #include <pbd/error.h>
-#include <pbd/lockmonitor.h>
 #include <pbd/pthread_utils.h>
 
 #include <ardour/configuration.h>
diff --git a/libs/ardour/session_midi.cc b/libs/ardour/session_midi.cc
index 91428a8ce4..9b6f0bf6ba 100644
--- a/libs/ardour/session_midi.cc
+++ b/libs/ardour/session_midi.cc
@@ -31,7 +31,7 @@
 #include <midi++/port.h>
 #include <midi++/manager.h>
 #include <pbd/error.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/pthread_utils.h>
 
 #include <ardour/configuration.h>
@@ -114,7 +114,7 @@ Session::set_midi_control (bool yn)
 	poke_midi_thread ();
 
 	if (_midi_port) {
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock guard (route_lock);
 		for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 			(*i)->reset_midi_control (_midi_port, midi_control);
 		}
@@ -607,7 +607,7 @@ Session::mmc_record_strobe (MIDI::MachineControl &mmc)
 		*/
 		
 		save_state ("", true);
-		atomic_set (&_record_status, Enabled);
+		g_atomic_int_set (&_record_status, Enabled);
 		RecordStateChanged (); /* EMIT SIGNAL */
 		
 		request_transport_speed (1.0);
@@ -789,7 +789,7 @@ Session::mmc_record_enable (MIDI::MachineControl &mmc, size_t trk, bool enabled)
 	if (mmc_control) {
 
 		RouteList::iterator i;
-		RWLockMonitor (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock guard (route_lock);
 		
 		for (i = routes.begin(); i != routes.end(); ++i) {
 			AudioTrack *at;
@@ -1073,8 +1073,8 @@ Session::deliver_mmc (MIDI::MachineControl::Command cmd, jack_nframes_t where)
 
 		mmc_buffer[nbytes++] = 0xf7; // terminate SysEx/MMC message
 
-		LockMonitor lm (midi_lock, __LINE__, __FILE__);
-
+		Glib::Mutex::Lock lm (midi_lock);
+		
 		if (_mmc_port->write (mmc_buffer, nbytes) != nbytes) {
 			error << string_compose(_("MMC: cannot send command %1%2%3"), &hex, cmd, &dec) << endmsg;
 		}
diff --git a/libs/ardour/session_process.cc b/libs/ardour/session_process.cc
index ba66d3ea2d..411c749ade 100644
--- a/libs/ardour/session_process.cc
+++ b/libs/ardour/session_process.cc
@@ -23,14 +23,13 @@
 #include <algorithm>
 #include <unistd.h>
 
-#include <ardour/timestamps.h>
-
 #include <pbd/error.h>
-#include <pbd/atomic.h>
-#include <pbd/lockmonitor.h>
+
+#include <glibmm/thread.h>
 
 #include <ardour/ardour.h>
 #include <ardour/session.h>
+#include <ardour/timestamps.h>
 #include <ardour/diskstream.h>
 #include <ardour/audioengine.h>
 #include <ardour/slave.h>
@@ -60,7 +59,7 @@ Session::process (jack_nframes_t nframes)
 	}
 
 	if (non_realtime_work_pending()) {
-		if (atomic_read (&butler_should_do_transport_work) == 0) {
+		if (g_atomic_int_get (&butler_should_do_transport_work) == 0) {
 			post_transport ();
 		} 
 	} 
@@ -95,7 +94,7 @@ Session::no_roll (jack_nframes_t nframes, jack_nframes_t offset)
 	   this is really bad ...
 	*/
 
-	if (atomic_read (&processing_prohibited)) {
+	if (g_atomic_int_get (&processing_prohibited)) {
 		for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 			(*i)->silence (nframes, offset);
 		}
@@ -232,15 +231,15 @@ Session::commit_diskstreams (jack_nframes_t nframes, bool &needs_butler)
 		cworst = min (cworst, (*i)->capture_buffer_load());
 	}
 
-	uint32_t pmin = atomic_read (&_playback_load);
-	uint32_t pminold = atomic_read (&_playback_load_min);
-	uint32_t cmin = atomic_read (&_capture_load);
-	uint32_t cminold = atomic_read (&_capture_load_min);
+	uint32_t pmin = g_atomic_int_get (&_playback_load);
+	uint32_t pminold = g_atomic_int_get (&_playback_load_min);
+	uint32_t cmin = g_atomic_int_get (&_capture_load);
+	uint32_t cminold = g_atomic_int_get (&_capture_load_min);
 
-	atomic_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
-	atomic_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
-	atomic_set (&_playback_load_min, min (pmin, pminold));
-	atomic_set (&_capture_load_min, min (cmin, cminold));
+	g_atomic_int_set (&_playback_load, (uint32_t) floor (pworst * 100.0f));
+	g_atomic_int_set (&_capture_load, (uint32_t) floor (cworst * 100.0f));
+	g_atomic_int_set (&_playback_load_min, min (pmin, pminold));
+	g_atomic_int_set (&_capture_load_min, min (cmin, cminold));
 
 	if (actively_recording()) {
 		set_dirty();
@@ -299,9 +298,9 @@ Session::process_with_events (jack_nframes_t nframes)
 	end_frame = _transport_frame + nframes;
 
 	{
-		TentativeRWLockMonitor rm (route_lock, false, __LINE__, __FILE__);
-		TentativeRWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
-	
+		Glib::RWLock::ReaderLock rm (route_lock, Glib::TRY_LOCK);
+		Glib::RWLock::ReaderLock dsm (diskstream_lock, Glib::TRY_LOCK);
+		
 		Event* this_event;
 		Events::iterator the_next_one;
 
@@ -570,8 +569,8 @@ Session::follow_slave (jack_nframes_t nframes, jack_nframes_t offset)
 		if (slave_state == Waiting) {
 
 			// cerr << "waiting at " << slave_transport_frame << endl;
-			TentativeRWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
-				
+			Glib::RWLock::ReaderLock dsm (diskstream_lock, Glib::TRY_LOCK);
+			
 			if (dsm.locked() && slave_transport_frame >= slave_wait_end) {
 				// cerr << "\tstart at " << _transport_frame << endl;
 
@@ -692,7 +691,7 @@ Session::follow_slave (jack_nframes_t nframes, jack_nframes_t offset)
 
 		bool need_butler;
 		
-		TentativeRWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock dsm (diskstream_lock, Glib::TRY_LOCK);
 		if (!dsm.locked()) {
 			goto noroll;
 		}
@@ -743,8 +742,8 @@ Session::process_without_events (jack_nframes_t nframes)
 	long frames_moved;
 	
 	{
-		TentativeRWLockMonitor rm (route_lock, false, __LINE__, __FILE__);
-		TentativeRWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock rm (route_lock, Glib::TRY_LOCK);
+		Glib::RWLock::ReaderLock dsm (diskstream_lock, Glib::TRY_LOCK);
 
 		if (!rm.locked() || !dsm.locked() || (post_transport_work & (PostTransportLocate|PostTransportStop))) {
 			no_roll (nframes, 0);
@@ -810,7 +809,7 @@ Session::process_without_events (jack_nframes_t nframes)
 void
 Session::process_audition (jack_nframes_t nframes)
 {
-	TentativeRWLockMonitor rm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock rm (route_lock, Glib::TRY_LOCK);
 	Event* ev;
 
 	if (rm.locked()) {
diff --git a/libs/ardour/session_state.cc b/libs/ardour/session_state.cc
index 602ac94314..466a546aee 100644
--- a/libs/ardour/session_state.cc
+++ b/libs/ardour/session_state.cc
@@ -44,14 +44,15 @@
 #include <sys/param.h>
 #endif
 
+#include <glibmm.h>
+
 #include <midi++/mmc.h>
 #include <midi++/port.h>
 #include <pbd/error.h>
-#include <pbd/dirname.h>
-#include <pbd/lockmonitor.h>
+
+#include <glibmm/thread.h>
 #include <pbd/pathscanner.h>
 #include <pbd/pthread_utils.h>
-#include <pbd/basename.h>
 #include <pbd/strsplit.h>
 
 #include <ardour/audioengine.h>
@@ -118,7 +119,7 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	_tempo_map = new TempoMap (_current_frame_rate);
 	_tempo_map->StateChanged.connect (mem_fun (*this, &Session::tempo_map_changed));
 
-	atomic_set (&processing_prohibited, 0);
+	g_atomic_int_set (&processing_prohibited, 0);
 	send_cnt = 0;
 	insert_cnt = 0;
 	_transport_speed = 0;
@@ -129,7 +130,7 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	end_location = new Location (0, 0, _("end"), Location::Flags ((Location::IsMark|Location::IsEnd)));
 	start_location = new Location (0, 0, _("start"), Location::Flags ((Location::IsMark|Location::IsStart)));
 	_end_location_is_free = true;
-	atomic_set (&_record_status, Disabled);
+	g_atomic_int_set (&_record_status, Disabled);
 	auto_play = false;
 	punch_in = false;
 	punch_out = false;
@@ -150,7 +151,7 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	state_was_pending = false;
 	set_next_event ();
 	outbound_mtc_smpte_frame = 0;
-	next_quarter_frame_to_send = 0;
+	next_quarter_frame_to_send = -1;
 	current_block_size = 0;
 	_solo_latched = true;
 	_solo_model = InverseMute;
@@ -170,12 +171,12 @@ Session::first_stage_init (string fullpath, string snapshot_name)
 	midi_control = true;
 	mmc = 0;
 	post_transport_work = PostTransportWork (0);
-	atomic_set (&butler_should_do_transport_work, 0);
-	atomic_set (&butler_active, 0);
-	atomic_set (&_playback_load, 100);
-	atomic_set (&_capture_load, 100);
-	atomic_set (&_playback_load_min, 100);
-	atomic_set (&_capture_load_min, 100);
+	g_atomic_int_set (&butler_should_do_transport_work, 0);
+	g_atomic_int_set (&butler_active, 0);
+	g_atomic_int_set (&_playback_load, 100);
+	g_atomic_int_set (&_capture_load, 100);
+	g_atomic_int_set (&_playback_load_min, 100);
+	g_atomic_int_set (&_capture_load_min, 100);
 	pending_audition_region = 0;
 	_edit_mode = Slide;
 	pending_edit_mode = _edit_mode;
@@ -297,11 +298,9 @@ Session::second_stage_init (bool new_session)
 		return -1;
 	}
 
-	/* FIXME
-	if (start_midi_thread ()) {
+	/*if (start_midi_thread ()) {
 		return -1;
-	}
-	*/
+	}*/
 
 	if (state_tree) {
 		if (set_state (*state_tree->root())) {
@@ -338,11 +337,10 @@ Session::second_stage_init (bool new_session)
 		first_time_running = _engine.Running.connect (mem_fun (*this, &Session::when_engine_running));
 	}
 
-	// FIXME
 	//send_full_time_code ();
 	_engine.transport_locate (0);
-	//deliver_mmc (MIDI::MachineControl::cmdMmcReset, 0);
-	//deliver_mmc (MIDI::MachineControl::cmdLocate, 0);
+	deliver_mmc (MIDI::MachineControl::cmdMmcReset, 0);
+	deliver_mmc (MIDI::MachineControl::cmdLocate, 0);
 
 	ControlProtocolManager::instance().set_session (*this);
 
@@ -1337,7 +1335,7 @@ Session::state(bool full_state)
 	child = node->add_child ("Sources");
 
 	if (full_state) {
-		LockMonitor sl (source_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock sl (source_lock);
 
 		for (SourceList::iterator siter = sources.begin(); siter != sources.end(); ++siter) {
 			
@@ -1366,7 +1364,7 @@ Session::state(bool full_state)
 	child = node->add_child ("Regions");
 
 	if (full_state) { 
-		LockMonitor rl (region_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock rl (region_lock);
 
 		for (AudioRegionList::const_iterator i = audio_regions.begin(); i != audio_regions.end(); ++i) {
 			
@@ -1381,7 +1379,7 @@ Session::state(bool full_state)
 	child = node->add_child ("DiskStreams");
 
 	{ 
-		RWLockMonitor dl (diskstream_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock dl (diskstream_lock);
 		for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 			if (!(*i)->hidden()) {
 				child->add_child_nocopy ((*i)->get_state());
@@ -1393,7 +1391,7 @@ Session::state(bool full_state)
 	
 	child = node->add_child ("Connections");
 	{
-		LockMonitor lm (connection_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (connection_lock);
 		for (ConnectionList::iterator i = _connections.begin(); i != _connections.end(); ++i) {
 			if (!(*i)->system_dependent()) {
 				child->add_child_nocopy ((*i)->get_state());
@@ -1403,7 +1401,7 @@ Session::state(bool full_state)
 
 	child = node->add_child ("Routes");
 	{
-		RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+		Glib::RWLock::ReaderLock lm (route_lock);
 		
 		RoutePublicOrderSorter cmp;
 		RouteList public_order(routes);
@@ -1806,7 +1804,7 @@ Session::get_sources_as_xml ()
 
 {
 	XMLNode* node = new XMLNode (X_("Sources"));
-	LockMonitor lm (source_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (source_lock);
 
 	for (SourceList::iterator i = sources.begin(); i != sources.end(); ++i) {
 		node->add_child_nocopy ((*i).second->get_state());
@@ -1961,7 +1959,7 @@ Session::refresh_disk_space ()
 #if HAVE_SYS_VFS_H
 	struct statfs statfsbuf;
 	vector<space_and_path>::iterator i;
-	LockMonitor lm (space_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (space_lock);
 	double scale;
 
 	/* get freespace on every FS that is part of the session path */
@@ -2402,7 +2400,7 @@ Session::load_route_groups (const XMLNode& node, bool edit)
 void
 Session::swap_configuration(Configuration** new_config)
 {
-	RWLockMonitor lm (route_lock, true, __LINE__, __FILE__); // jlc - WHY?
+	Glib::RWLock::WriterLock lm (route_lock); // jlc - WHY?
 	Configuration* tmp = *new_config;
 	*new_config = Config;
 	Config = tmp;
@@ -2412,7 +2410,7 @@ Session::swap_configuration(Configuration** new_config)
 void
 Session::copy_configuration(Configuration* new_config)
 {
-	RWLockMonitor lm (route_lock, true, __LINE__, __FILE__);
+	Glib::RWLock::WriterLock lm (route_lock);
 	new_config = new Configuration(*Config);
 }
 
@@ -2591,7 +2589,7 @@ Session::GlobalRouteBooleanState
 Session::get_global_route_boolean (bool (Route::*method)(void) const)
 {
 	GlobalRouteBooleanState s;
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
 
 	for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 		if (!(*i)->hidden()) {
@@ -2611,7 +2609,7 @@ Session::GlobalRouteMeterState
 Session::get_global_route_metering ()
 {
 	GlobalRouteMeterState s;
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
 
 	for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 		if (!(*i)->hidden()) {
@@ -3068,13 +3066,13 @@ Session::cleanup_sources (Session::cleanup_report& rep)
 		   on whichever filesystem it was already on.
 		*/
 
-		newpath = PBD::dirname (*x);
-		newpath = PBD::dirname (newpath);
+		newpath = Glib::path_get_dirname (*x);
+		newpath = Glib::path_get_dirname (newpath);
 
 		newpath += '/';
 		newpath += dead_sound_dir_name;
 		newpath += '/';
-		newpath += PBD::basename ((*x));
+		newpath += Glib::path_get_basename ((*x));
 		
 		if (access (newpath.c_str(), F_OK) == 0) {
 			
diff --git a/libs/ardour/session_transport.cc b/libs/ardour/session_transport.cc
index 45ef3812d1..fafaf2a475 100644
--- a/libs/ardour/session_transport.cc
+++ b/libs/ardour/session_transport.cc
@@ -27,7 +27,7 @@
 
 #include <pbd/undo.h>
 #include <pbd/error.h>
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/pthread_utils.h>
 
 #include <midi++/mmc.h>
@@ -190,9 +190,9 @@ Session::realtime_stop (bool abort)
 void
 Session::butler_transport_work ()
 {
-	RWLockMonitor rm (route_lock, false, __LINE__, __FILE__);
-	RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
-		
+	Glib::RWLock::ReaderLock rm (route_lock);
+	Glib::RWLock::ReaderLock dsm (diskstream_lock);
+	
 	if (post_transport_work & PostTransportCurveRealloc) {
 		for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
 			(*i)->curve_reallocate();
@@ -240,13 +240,13 @@ Session::butler_transport_work ()
 		non_realtime_set_audition ();
 	}
 
-	atomic_dec (&butler_should_do_transport_work);
+	g_atomic_int_dec_and_test (&butler_should_do_transport_work);
 }
 
 void
 Session::non_realtime_set_speed ()
 {
-	RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
 	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		(*i)->non_realtime_set_speed ();
@@ -256,7 +256,7 @@ Session::non_realtime_set_speed ()
 void
 Session::non_realtime_overwrite ()
 {
-	RWLockMonitor lm (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (diskstream_lock);
 
 	for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 		if ((*i)->pending_overwrite) {
@@ -398,9 +398,9 @@ Session::non_realtime_stop (bool abort)
 		*/
 
 		if (!Config->get_latched_record_enable()) {
-			atomic_set (&_record_status, Disabled);
+			g_atomic_int_set (&_record_status, Disabled);
 		} else {
-			atomic_set (&_record_status, Enabled);
+			g_atomic_int_set (&_record_status, Enabled);
 		}
 		RecordStateChanged (); /* emit signal */
 	}
@@ -633,7 +633,7 @@ Session::locate (jack_nframes_t target_frame, bool with_roll, bool with_flush, b
 
 		/* this is functionally what clear_clicks() does but with a tentative lock */
 
-		TentativeRWLockMonitor clickm (click_lock, true, __LINE__, __FILE__);
+		Glib::RWLock::WriterLock clickm (click_lock, Glib::TRY_LOCK);
 	
 		if (clickm.locked()) {
 			
@@ -652,7 +652,7 @@ Session::locate (jack_nframes_t target_frame, bool with_roll, bool with_flush, b
 			   a non-tentative rwlock here,  because the action must occur.
 			   The rarity and short potential lock duration makes this "OK"
 			*/
-			RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching from input" << __FILE__ << __LINE__ << endl << endl;
@@ -667,7 +667,7 @@ Session::locate (jack_nframes_t target_frame, bool with_roll, bool with_flush, b
 			   a non-tentative rwlock here,  because the action must occur.
 			   The rarity and short potential lock duration makes this "OK"
 			*/
-			RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching to input" << __FILE__ << __LINE__ << endl << endl;
@@ -713,7 +713,7 @@ Session::set_transport_speed (float speed, bool abort)
 			   a non-tentative rwlock here,  because the action must occur.
 			   The rarity and short potential lock duration makes this "OK"
 			*/
-			RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if ((*i)->record_enabled ()) {
 					//cerr << "switching to input" << __FILE__ << __LINE__ << endl << endl;
@@ -739,7 +739,7 @@ Session::set_transport_speed (float speed, bool abort)
 			   a non-tentative rwlock here,  because the action must occur.
 			   The rarity and short potential lock duration makes this "OK"
 			*/
-			RWLockMonitor dsm (diskstream_lock, false, __LINE__, __FILE__);
+			Glib::RWLock::ReaderLock dsm (diskstream_lock);
 			for (DiskStreamList::iterator i = diskstreams.begin(); i != diskstreams.end(); ++i) {
 				if (auto_input && (*i)->record_enabled ()) {
 					//cerr << "switching from input" << __FILE__ << __LINE__ << endl << endl;
@@ -1171,7 +1171,7 @@ Session::engine_halted ()
 	   the picture.
 	*/
 
-	atomic_set (&butler_should_do_transport_work, 0);
+	g_atomic_int_set (&butler_should_do_transport_work, 0);
 	post_transport_work = PostTransportWork (0);
 	stop_butler ();
 	
@@ -1207,8 +1207,8 @@ Session::update_latency_compensation (bool with_stop, bool abort)
 		return;
 	}
 
-	RWLockMonitor lm (route_lock, false, __LINE__, __FILE__);
-	RWLockMonitor lm2 (diskstream_lock, false, __LINE__, __FILE__);
+	Glib::RWLock::ReaderLock lm (route_lock);
+	Glib::RWLock::ReaderLock lm2 (diskstream_lock);
 	_worst_track_latency = 0;
 
 	for (RouteList::iterator i = routes.begin(); i != routes.end(); ++i) {
diff --git a/libs/ardour/sndfilesource.cc b/libs/ardour/sndfilesource.cc
index e547b212a0..87f7faf423 100644
--- a/libs/ardour/sndfilesource.cc
+++ b/libs/ardour/sndfilesource.cc
@@ -138,7 +138,7 @@ SndFileSource::read (Sample *dst, jack_nframes_t start, jack_nframes_t cnt, char
 	real_cnt = cnt * _info.channels;
 
 	{
-		LockMonitor lm (_tmpbuf_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (_tmpbuf_lock);
 		
 		if (tmpbufsize < real_cnt) {
 			
diff --git a/libs/ardour/source.cc b/libs/ardour/source.cc
index ffb067733d..7d790a036d 100644
--- a/libs/ardour/source.cc
+++ b/libs/ardour/source.cc
@@ -29,7 +29,7 @@
 #include <iomanip>
 #include <algorithm>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/xml++.h>
 #include <pbd/pthread_utils.h>
 
@@ -41,13 +41,12 @@ using std::min;
 using std::max;
 
 using namespace ARDOUR;
-using namespace PBD;
 
-sigc::signal<void,Source *> Source::SourceCreated;
+sigc::signal<void,Source *>  Source::SourceCreated;
 pthread_t                    Source::peak_thread;
 bool                         Source::have_peak_thread = false;
 vector<Source*>              Source::pending_peak_sources;
-PBD::Lock                    Source::pending_peak_sources_lock;
+Glib::StaticMutex            Source::pending_peak_sources_lock = GLIBMM_STATIC_MUTEX_INIT;
 int                          Source::peak_request_pipe[2];
 
 bool Source::_build_missing_peakfiles = false;
@@ -142,19 +141,19 @@ Source::peak_thread_work (void* arg)
 	PBD::ThreadCreated (pthread_self(), X_("Peak"));
 	struct pollfd pfd[1];
 
-	LockMonitor lm (pending_peak_sources_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (pending_peak_sources_lock);
 
 	while (true) {
 
 		pfd[0].fd = peak_request_pipe[0];
 		pfd[0].events = POLLIN|POLLERR|POLLHUP;
 
-		pthread_mutex_unlock (pending_peak_sources_lock.mutex());
+		pending_peak_sources_lock.unlock();
 
 		if (poll (pfd, 1, -1) < 0) {
 
 			if (errno == EINTR) {
-				pthread_mutex_lock (pending_peak_sources_lock.mutex());
+				pending_peak_sources_lock.lock();
 				continue;
 			}
 			
@@ -204,16 +203,16 @@ Source::peak_thread_work (void* arg)
 			}
 		}
 
-		pthread_mutex_lock (pending_peak_sources_lock.mutex());
+		pending_peak_sources_lock.lock();
 
 		while (!pending_peak_sources.empty()) {
 
 			Source* s = pending_peak_sources.front();
 			pending_peak_sources.erase (pending_peak_sources.begin());
 
-			pthread_mutex_unlock (pending_peak_sources_lock.mutex());
+			pending_peak_sources_lock.unlock();
 			s->build_peaks();
-			pthread_mutex_lock (pending_peak_sources_lock.mutex());
+			pending_peak_sources_lock.lock();
 		}
 	}
 
@@ -272,7 +271,7 @@ Source::queue_for_peaks (Source& source)
 {
 	if (have_peak_thread) {
 
-		LockMonitor lm (pending_peak_sources_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (pending_peak_sources_lock);
 
 		source.next_peak_clear_should_notify = true;
 
@@ -291,7 +290,7 @@ void Source::clear_queue_for_peaks ()
 {
 	/* this is done to cancel a group of running peak builds */
 	if (have_peak_thread) {
-		LockMonitor lm (pending_peak_sources_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (pending_peak_sources_lock);
 		pending_peak_sources.clear ();
 	}
 }
@@ -301,7 +300,7 @@ bool
 Source::peaks_ready (sigc::slot<void> the_slot, sigc::connection& conn) const
 {
 	bool ret;
-	LockMonitor lm (_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_lock);
 
 	/* check to see if the peak data is ready. if not
 	   connect the slot while still holding the lock.
@@ -388,7 +387,7 @@ Source::initialize_peakfile (bool newfile, string audio_path)
 int 
 Source::read_peaks (PeakData *peaks, jack_nframes_t npeaks, jack_nframes_t start, jack_nframes_t cnt, double samples_per_visual_peak) const
 {
-	LockMonitor lm (_lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (_lock);
 	double scale;
 	double expected_peaks;
 	PeakData::PeakDatum xmax;
@@ -699,7 +698,7 @@ Source::build_peaks ()
 	list<PeakBuildRecord*> copy;
 
 	{
-		LockMonitor lm (_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (_lock);
 		copy = pending_peak_builds;
 		pending_peak_builds.clear ();
 	}
@@ -719,7 +718,7 @@ Source::build_peaks ()
 	}
 
 	{ 
-		LockMonitor lm (_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (_lock);
 
 		if (status == 0) {
 			_peaks_built = true;
@@ -830,7 +829,7 @@ Source::do_build_peak (jack_nframes_t first_frame, jack_nframes_t cnt)
 void
 Source::build_peaks_from_scratch ()
 {
-	LockMonitor lp (_lock, __LINE__, __FILE__); 
+	Glib::Mutex::Lock lp (_lock); 
 
 	next_peak_clear_should_notify = true;
 	pending_peak_builds.push_back (new PeakBuildRecord (0, _length));
@@ -883,7 +882,7 @@ Source::available_peaks (double zoom_factor) const
 	}
 
 	{ 
-		LockMonitor lm (_lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (_lock);
 		end = lseek (peakfile, 0, SEEK_END);
 	}
 
diff --git a/libs/ardour/tempo.cc b/libs/ardour/tempo.cc
index 5d6365cff3..64964b29dd 100644
--- a/libs/ardour/tempo.cc
+++ b/libs/ardour/tempo.cc
@@ -25,7 +25,7 @@
 
 #include <sigc++/bind.h>
 
-#include <pbd/lockmonitor.h>
+#include <glibmm/thread.h>
 #include <pbd/xml++.h>
 #include <ardour/tempo.h>
 #include <ardour/utils.h>
@@ -240,7 +240,7 @@ TempoMap::move_metric_section (MetricSection& section, const BBT_Time& when)
 		return 1;
 	}
 
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	MetricSectionSorter cmp;
 	BBT_Time corrected (when);
 	
@@ -283,7 +283,7 @@ TempoMap::remove_tempo (const TempoSection& tempo)
 	bool removed = false;
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		Metrics::iterator i;
 
 		for (i = metrics->begin(); i != metrics->end(); ++i) {
@@ -310,7 +310,7 @@ TempoMap::remove_meter (const MeterSection& tempo)
 	bool removed = false;
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		Metrics::iterator i;
 
 		for (i = metrics->begin(); i != metrics->end(); ++i) {
@@ -361,7 +361,7 @@ void
 TempoMap::add_tempo (const Tempo& tempo, BBT_Time where)
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		/* new tempos always start on a beat */
 	
@@ -381,7 +381,7 @@ TempoMap::replace_tempo (TempoSection& existing, const Tempo& replacement)
 	bool replaced = false;
 
 	{ 
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		Metrics::iterator i;
 		
 		for (i = metrics->begin(); i != metrics->end(); ++i) {
@@ -411,7 +411,7 @@ void
 TempoMap::add_meter (const Meter& meter, BBT_Time where)
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		/* a new meter always starts a new bar on the first beat. so
 		   round the start time appropriately. remember that
@@ -443,7 +443,7 @@ TempoMap::replace_meter (MeterSection& existing, const Meter& replacement)
 	bool replaced = false;
 
 	{ 
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		Metrics::iterator i;
 		
 		for (i = metrics->begin(); i != metrics->end(); ++i) {
@@ -611,7 +611,7 @@ TempoMap::metric_at (BBT_Time bbt) const
 void
 TempoMap::bbt_time (jack_nframes_t frame, BBT_Time& bbt) const
 {
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	bbt_time_unlocked (frame, bbt);
 }
 
@@ -759,7 +759,7 @@ TempoMap::bbt_duration_at (jack_nframes_t pos, const BBT_Time& bbt, int dir) con
 	bbt_time(pos,when);
 
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 		frames = bbt_duration_at_unlocked (when, bbt,dir);
 	}
 
@@ -896,7 +896,7 @@ TempoMap::bbt_duration_at_unlocked (const BBT_Time& when, const BBT_Time& bbt, i
 jack_nframes_t
 TempoMap::round_to_bar (jack_nframes_t fr, int dir)
 {
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	return round_to_type (fr, dir, Bar);
 }
 
@@ -904,7 +904,7 @@ TempoMap::round_to_bar (jack_nframes_t fr, int dir)
 jack_nframes_t
 TempoMap::round_to_beat (jack_nframes_t fr, int dir)
 {
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	return round_to_type (fr, dir, Beat);
 }
 
@@ -912,7 +912,7 @@ jack_nframes_t
 
 TempoMap::round_to_beat_subdivision (jack_nframes_t fr, int sub_num)
 {
-        LockMonitor lm (lock, __LINE__, __FILE__);
+        Glib::Mutex::Lock lm (lock);
         TempoMap::BBTPointList::iterator i;
         TempoMap::BBTPointList *more_zoomed_bbt_points;
         jack_nframes_t frame_one_beats_worth;
@@ -1185,7 +1185,7 @@ TempoMap::meter_at (jack_nframes_t frame)
 XMLNode&
 TempoMap::get_state ()
 {
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 	Metrics::const_iterator i;
 	XMLNode *root = new XMLNode ("TempoMap");
 
@@ -1200,7 +1200,7 @@ int
 TempoMap::set_state (const XMLNode& node)
 {
 	{
-		LockMonitor lm (lock, __LINE__, __FILE__);
+		Glib::Mutex::Lock lm (lock);
 
 		XMLNodeList nlist;
 		XMLNodeConstIterator niter;
@@ -1292,7 +1292,7 @@ TempoMap::get_memento () const
 Change
 TempoMap::restore_state (StateManager::State& state)
 {
-	LockMonitor lm (lock, __LINE__, __FILE__);
+	Glib::Mutex::Lock lm (lock);
 
 	TempoMapState* tmstate = dynamic_cast<TempoMapState*> (&state);
 
diff --git a/libs/ardour/utils.cc b/libs/ardour/utils.cc
index 8e9a36de59..15d0c6be81 100644
--- a/libs/ardour/utils.cc
+++ b/libs/ardour/utils.cc
@@ -175,10 +175,13 @@ tokenize_fullpath (string fullpath, string& path, string& name)
 }
 
 int
-touch_file(string path)
+touch_file (string path)
 {
-	FILE* file = fopen(path.c_str(), "a");
-	fclose(file);
+	int fd = open (path.c_str(), O_RDONLY|O_CREAT);
+	if (fd >= 0) {
+		close (fd);
+		return 0;
+	}
 	return 1;
 }