* unix/tclUnixNotfy.c (Tcl_FinalizeNotifier, NotifierThreadProc):

	added write of 'q' into triggerPipe for notifier in threaded case,
	so that Tcl doesn't hang when children are still running [Bug: 4139]

	* unix/tclUnixThrd.c (Tcl_MutexLock): minor comment fixes.

3 files changed, 58 insertions, 32 deletions

diff --git a/ChangeLog b/ChangeLog
index 5da8d38..5315917 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,26 +1,34 @@
+2000-04-24  Jeff Hobbs  <hobbs@scriptics.com>
+
+	* unix/tclUnixNotfy.c (Tcl_FinalizeNotifier, NotifierThreadProc):
+	added write of 'q' into triggerPipe for notifier in threaded case,
+	so that Tcl doesn't hang when children are still running [Bug: 4139]
+
+	* unix/tclUnixThrd.c (Tcl_MutexLock): minor comment fixes.
+
 2000-04-23  Jim Ingham  <jingham@cygnus.com>
 
-        These changes make some error handling marginally better for Mac sockets.  It is
-        still somewhat flakey, however.
-
-        * mac/tclMacSock.c (TcpClose): Add timeouts to the close - these don't seem to
-        be honored, however.
-        * Use a separate PB for the release, since an async connect socket will still
-        be using the original buffer.
-        * Make sure TCPRelease returns noErr before freeing the recvBuff.  If the call
-        returns an error, then the buffer is not right.
-        * mac/tclMacSocket.c (CreateSocket): Add timeouts to the async create.  These
-        don't seem to trigger, however.  Sigh...
-        * mac/tclMacSocket.c (WaitForSocketEvent): If an TCP_ASYNC_CONNECT socket errors
-        out, then return EWOULDBLOCK & error out.
-        * mac/tclMacSock.c: (NotifyRoutine) Added a NotifyRoutine for experimenting 
-        with MacTCP.
-            
+	These changes make some error handling marginally better for Mac
+	sockets.  It is still somewhat flakey, however.
+
+	* mac/tclMacSock.c (TcpClose): Add timeouts to the close - these
+	don't seem to be honored, however.
+	Use a separate PB for the release, since an async connect socket
+	will still be using the original buffer.
+	Make sure TCPRelease returns noErr before freeing the recvBuff.
+	If the call returns an error, then the buffer is not right.
+	* mac/tclMacSock.c (CreateSocket): Add timeouts to the async
+	create. These don't seem to trigger, however.  Sigh...
+	* mac/tclMacSock.c (WaitForSocketEvent): If an TCP_ASYNC_CONNECT
+	socket errors out, then return EWOULDBLOCK & error out.
+	* mac/tclMacSock.c (NotifyRoutine): Added a NotifyRoutine for
+	experimenting with MacTCP.
+
 2000-04-22  Jim Ingham <jingham@cygnus.com>
 
-        * library/package.tcl (tclPkgUnknown): Fixed a typo in the Mac package
-        search part of tclPkgUnknown.
-        
+	* library/package.tcl (tclPkgUnknown): Fixed a typo in the Mac package
+	search part of tclPkgUnknown.
+
 2000-04-21  Sandeep Tamhankar <sandeep@scriptics.com>
 
 	* library/http2.1/http.tcl: Fixed a newly introduced bug where if
diff --git a/unix/tclUnixNotfy.c b/unix/tclUnixNotfy.c
index 7d63228..f376746 100644
--- a/unix/tclUnixNotfy.c
+++ b/unix/tclUnixNotfy.c
@@ -11,7 +11,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclUnixNotfy.c,v 1.9 2000/04/09 16:04:20 kupries Exp $
+ * RCS: @(#) $Id: tclUnixNotfy.c,v 1.10 2000/04/24 23:32:13 hobbs Exp $
  */
 
 #include "tclInt.h"
@@ -264,7 +264,20 @@ Tcl_FinalizeNotifier(clientData)
 	if (triggerPipe < 0) {
 	    panic("Tcl_FinalizeNotifier: notifier pipe not initialized");
 	}
+
+        /*
+	 * Send "q" message to the notifier thread so that it will
+	 * terminate.  The notifier will return from its call to select()
+	 * and notice that a "q" message has arrived, it will then close
+	 * its side of the pipe and terminate its thread.  Note the we can
+	 * not just close the pipe and check for EOF in the notifier
+	 * thread because if a background child process was created with
+	 * exec, select() would not register the EOF on the pipe until the
+	 * child processes had terminated. [Bug: 4139]
+	 */
+	write(triggerPipe, "q", 1);
 	close(triggerPipe);
+
 	Tcl_ConditionWait(&notifierCV, &notifierMutex, NULL);
     }
 
@@ -963,10 +976,10 @@ NotifierThreadProc(clientData)
 		Tcl_ConditionNotify(&tsdPtr->waitCV);
 		if (tsdPtr->onList) {
 		    /*
-		     * Remove the ThreadSpecificData structure of this thread
-		     * from the waiting list. This prevents us from continuously
-		     * spining on select until the other threads runs and
-		     * services the file event.
+		     * Remove the ThreadSpecificData structure of this
+		     * thread from the waiting list. This prevents us from
+		     * continuously spining on select until the other
+		     * threads runs and services the file event.
 		     */
 	    
 		    if (tsdPtr->prevPtr) {
@@ -991,13 +1004,18 @@ NotifierThreadProc(clientData)
 	 * to avoid a race condition we only read one at a time.
 	 */
 
-	if ((masks[index] & bit) && (read(receivePipe, buf, 1) == 0)) {
-	    /*
-	     * Someone closed the write end of the pipe so we need to
-	     * shut down the notifier thread.
-	     */
+	if (masks[index] & bit) {
+	    i = read(receivePipe, buf, 1);
 
-	    break;
+	    if ((i == 0) || ((i == 1) && (buf[0] == 'q'))) {
+		/*
+		 * Someone closed the write end of the pipe or sent us a
+		 * Quit message [Bug: 4139] and then closed the write end
+		 * of the pipe so we need to shut down the notifier thread.
+		 */
+
+		break;
+	    }
 	}
     }
 
diff --git a/unix/tclUnixThrd.c b/unix/tclUnixThrd.c
index f4a5dca..16e2315 100644
--- a/unix/tclUnixThrd.c
+++ b/unix/tclUnixThrd.c
@@ -356,7 +356,7 @@ Tcl_MutexLock(mutexPtr)
 	MASTER_LOCK;
 	if (*mutexPtr == NULL) {
 	    /* 
-	     * Double inside master lock check to avoid a race.
+	     * Double inside master lock check to avoid a race condition.
 	     */
     
 	    pmutexPtr = (pthread_mutex_t *)ckalloc(sizeof(pthread_mutex_t));
@@ -374,7 +374,7 @@ Tcl_MutexLock(mutexPtr)
 /*
  *----------------------------------------------------------------------
  *
- * TclpMutexUnlock --
+ * Tcl_MutexUnlock --
  *
  *	This procedure is invoked to unlock a mutex.  The mutex must
  *	have been locked by Tcl_MutexLock.