Index: common/JackExternalClient.h
===================================================================
--- common/JackExternalClient.h	(revision 1038)
+++ common/JackExternalClient.h	(working copy)
@@ -46,7 +46,7 @@
         JackExternalClient();
         virtual ~JackExternalClient();
 
-        int Open(const char* name, int refnum, int* shared_client);
+        int Open(const char* name, int pid, int refnum, int* shared_client);
         int Close();
 
         int ClientNotify(int refnum, const char* name, int notify, int sync, int value1, int value2);
Index: common/JackRequest.h
===================================================================
--- common/JackRequest.h	(revision 1038)
+++ common/JackRequest.h	(working copy)
@@ -193,23 +193,29 @@
 {
 
     char fName[JACK_CLIENT_NAME_SIZE + 1];
+    int fPID;
 
     JackClientOpenRequest()
     {}
-    JackClientOpenRequest(const char* name): JackRequest(JackRequest::kClientOpen)
+    JackClientOpenRequest(const char* name, int pid): JackRequest(JackRequest::kClientOpen)
     {
         snprintf(fName, sizeof(fName), "%s", name);
+        fPID = pid;
     }
 
     int Read(JackChannelTransaction* trans)
     {
-        return trans->Read(&fName, JACK_CLIENT_NAME_SIZE + 1);
+        CheckRes(trans->Read(&fName, JACK_CLIENT_NAME_SIZE + 1));
+        CheckRes(trans->Read(&fPID, sizeof(fPID)));
+        return 0;
     }
 
     int Write(JackChannelTransaction* trans)
     {
         CheckRes(JackRequest::Write(trans));
-        return trans->Write(&fName, JACK_CLIENT_NAME_SIZE + 1);
+        CheckRes(trans->Write(&fName, JACK_CLIENT_NAME_SIZE + 1));
+        CheckRes(trans->Write(&fPID, sizeof(fPID)));
+        return 0;
     }
 };
 
Index: common/JackEngine.cpp
===================================================================
--- common/JackEngine.cpp	(revision 1038)
+++ common/JackEngine.cpp	(working copy)
@@ -448,7 +448,7 @@
 }
 
 // Used for external clients
-int JackEngine::ClientExternalOpen(const char* name, int* ref, int* shared_engine, int* shared_client, int* shared_graph_manager)
+int JackEngine::ClientExternalOpen(const char* name, int pid, int* ref, int* shared_engine, int* shared_client, int* shared_graph_manager)
 {
     jack_log("JackEngine::ClientOpen: name = %s ", name);
 
@@ -465,7 +465,7 @@
         goto error;
     }
 
-    if (client->Open(name, refnum, shared_client) < 0) {
+    if (client->Open(name, pid, refnum, shared_client) < 0) {
         jack_error("Cannot open client");
         goto error;
     }
Index: common/JackSocketServerChannel.h
===================================================================
--- common/JackSocketServerChannel.h	(revision 1038)
+++ common/JackSocketServerChannel.h	(working copy)
@@ -49,7 +49,7 @@
         void BuildPoolTable();
 
         void ClientCreate();
-        void ClientAdd(int fd, char* name, int* shared_engine, int* shared_client, int* shared_graph, int* result);
+        void ClientAdd(int fd, char* name, int pid, int* shared_engine, int* shared_client, int* shared_graph, int* result);
         void ClientRemove(int fd, int refnum);
         void ClientKill(int fd);
 
Index: common/JackSocketClientChannel.cpp
===================================================================
--- common/JackSocketClientChannel.cpp	(revision 1038)
+++ common/JackSocketClientChannel.cpp	(working copy)
@@ -22,6 +22,7 @@
 #include "JackClient.h"
 #include "JackGlobals.h"
 #include "JackError.h"
+#include "JackTools.h"
 
 namespace Jack
 {
@@ -151,7 +152,7 @@
 
 void JackSocketClientChannel::ClientOpen(const char* name, int* shared_engine, int* shared_client, int* shared_graph, int* result)
 {
-    JackClientOpenRequest req(name);
+    JackClientOpenRequest req(name, JackTools::GetPID());
     JackClientOpenResult res;
     ServerSyncCall(&req, &res, result);
     *shared_engine = res.fSharedEngine;
Index: common/JackSocketServerChannel.cpp
===================================================================
--- common/JackSocketServerChannel.cpp	(revision 1038)
+++ common/JackSocketServerChannel.cpp	(working copy)
@@ -89,11 +89,11 @@
     }
 }
 
-void JackSocketServerChannel::ClientAdd(int fd, char* name, int* shared_engine, int* shared_client, int* shared_graph, int* result)
+void JackSocketServerChannel::ClientAdd(int fd, char* name, int pid, int* shared_engine, int* shared_client, int* shared_graph, int* result)
 {
     jack_log("JackSocketServerChannel::ClientAdd");
     int refnum = -1;
-    *result = fServer->GetEngine()->ClientExternalOpen(name, &refnum, shared_engine, shared_client, shared_graph);
+    *result = fServer->GetEngine()->ClientExternalOpen(name, pid, &refnum, shared_engine, shared_client, shared_graph);
     if (*result == 0) {
         fSocketTable[fd].first = refnum;
         fRebuild = true;
@@ -167,7 +167,7 @@
             JackClientOpenRequest req;
             JackClientOpenResult res;
             if (req.Read(socket) == 0)
-                ClientAdd(fd, req.fName, &res.fSharedEngine, &res.fSharedClient, &res.fSharedGraph, &res.fResult);
+                ClientAdd(fd, req.fName, req.fPID, &res.fSharedEngine, &res.fSharedClient, &res.fSharedGraph, &res.fResult);
             if (res.Write(socket) < 0)
                 jack_error("JackRequest::kClientOpen write error name = %s", req.fName);
             break;
Index: common/JackEngine.h
===================================================================
--- common/JackEngine.h	(revision 1038)
+++ common/JackEngine.h	(working copy)
@@ -80,7 +80,7 @@
 
         // Client management
         virtual int ClientCheck(const char* name, char* name_res, int protocol, int options, int* status);
-        virtual int ClientExternalOpen(const char* name, int* ref, int* shared_engine, int* shared_client, int* shared_graph_manager);
+        virtual int ClientExternalOpen(const char* name, int pid, int* ref, int* shared_engine, int* shared_client, int* shared_graph_manager);
         virtual int ClientInternalOpen(const char* name, int* ref, JackEngineControl** shared_engine, JackGraphManager** shared_manager, JackClientInterface* client, bool wait);
 
         virtual int ClientExternalClose(int refnum);
Index: common/JackLockedEngine.h
===================================================================
--- common/JackLockedEngine.h	(revision 1038)
+++ common/JackLockedEngine.h	(working copy)
@@ -62,10 +62,10 @@
             JackLock lock(this);
             return fEngine->ClientCheck(name, name_res, protocol, options, status);
         }
-        int ClientExternalOpen(const char* name, int* ref, int* shared_engine, int* shared_client, int* shared_graph_manager)
+        int ClientExternalOpen(const char* name, int pid, int* ref, int* shared_engine, int* shared_client, int* shared_graph_manager)
         {
             JackLock lock(this);
-            return fEngine->ClientExternalOpen(name, ref, shared_engine, shared_client, shared_graph_manager);
+            return fEngine->ClientExternalOpen(name, pid, ref, shared_engine, shared_client, shared_graph_manager);
         }
         int ClientInternalOpen(const char* name, int* ref, JackEngineControl** shared_engine, JackGraphManager** shared_manager, JackClientInterface* client, bool wait)
         {
Index: common/JackExternalClient.cpp
===================================================================
--- common/JackExternalClient.cpp	(revision 1038)
+++ common/JackExternalClient.cpp	(working copy)
@@ -45,8 +45,9 @@
     return result;
 }
 
-int JackExternalClient::Open(const char* name, int refnum, int* shared_client)
+int JackExternalClient::Open(const char* name, int pid, int refnum, int* shared_client)
 {
+    jack_info("client '%s' with pid %d", name, pid);
     try {
 
         if (fChannel->Open(name) < 0) {
Index: common/jack/jack.h
===================================================================
--- common/jack/jack.h	(revision 1038)
+++ common/jack/jack.h	(working copy)
@@ -135,6 +135,11 @@
     char * jack_get_client_name (jack_client_t *client);
 
     /**
+     * @return pid of client. If not available, 0 will be returned.
+     */
+    int jack_get_client_pid (const char *name);
+
+    /**
      * Load an internal client into the Jack server.
      *
      * Internal clients run inside the JACK server process.  They can use
Index: macosx/JackMachServerChannel.cpp
===================================================================
--- macosx/JackMachServerChannel.cpp	(revision 1038)
+++ macosx/JackMachServerChannel.cpp	(working copy)
@@ -88,7 +88,7 @@
 void JackMachServerChannel::ClientOpen(char* name, mach_port_t* private_port, int* shared_engine, int* shared_client, int* shared_graph, int* result)
 {
     int refnum = -1;
-    *result = GetEngine()->ClientExternalOpen(name, &refnum, shared_engine, shared_client, shared_graph);
+    *result = GetEngine()->ClientExternalOpen(name, 0, &refnum, shared_engine, shared_client, shared_graph);
 
     if (*result == 0) {
         mach_port_t port = fServerPort.AddPort();
Index: windows/JackWinNamedPipeClientChannel.cpp
===================================================================
--- windows/JackWinNamedPipeClientChannel.cpp	(revision 1038)
+++ windows/JackWinNamedPipeClientChannel.cpp	(working copy)
@@ -155,7 +155,7 @@
 
 void JackWinNamedPipeClientChannel::ClientOpen(const char* name, int* shared_engine, int* shared_client, int* shared_graph, int* result)
 {
-    JackClientOpenRequest req(name);
+    JackClientOpenRequest req(name, JackTools::GetPID());
     JackClientOpenResult res;
     ServerSyncCall(&req, &res, result);
     *shared_engine = res.fSharedEngine;
Index: windows/JackWinNamedPipeServerChannel.cpp
===================================================================
--- windows/JackWinNamedPipeServerChannel.cpp	(revision 1038)
+++ windows/JackWinNamedPipeServerChannel.cpp	(working copy)
@@ -122,7 +122,7 @@
                 JackClientOpenRequest req;
                 JackClientOpenResult res;
                 if (req.Read(fPipe) == 0)
-                    ClientAdd(req.fName, &res.fSharedEngine, &res.fSharedClient, &res.fSharedGraph, &res.fResult);
+                    ClientAdd(req.fName, req.fPID, &res.fSharedEngine, &res.fSharedClient, &res.fSharedGraph, &res.fResult);
                 res.Write(fPipe);
                 break;
             }
@@ -318,11 +318,11 @@
     return ret;
 }
 
-void JackClientPipeThread::ClientAdd(char* name, int* shared_engine, int* shared_client, int* shared_graph, int* result)
+void JackClientPipeThread::ClientAdd(char* name, int pid, int* shared_engine, int* shared_client, int* shared_graph, int* result)
 {
     jack_log("JackClientPipeThread::ClientAdd %s", name);
     fRefNum = -1;
-    *result = fServer->GetEngine()->ClientExternalOpen(name, &fRefNum, shared_engine, shared_client, shared_graph);
+    *result = fServer->GetEngine()->ClientExternalOpen(name, pid, &fRefNum, shared_engine, shared_client, shared_graph);
 }
 
 void JackClientPipeThread::ClientRemove()