Index: unix/tclUnixPipe.c
===================================================================
RCS file: /cvsroot/tcl/tcl/unix/tclUnixPipe.c,v
retrieving revision 1.9.2.1
diff -u -r1.9.2.1 tclUnixPipe.c
--- unix/tclUnixPipe.c	2001/04/03 22:54:39	1.9.2.1
+++ unix/tclUnixPipe.c	2001/06/29 22:36:49
@@ -378,7 +378,7 @@
 	newArgv[i] = Tcl_UtfToExternalDString(NULL, argv[i], -1, &dsArray[i]);
     }
 
-    joinThisError = (errorFile == outputFile);
+    joinThisError = errorFile && (errorFile == outputFile);
     pid = fork();
     if (pid == 0) {
 	fd = GetFd(errPipeOut);
