diff -ruN pbs-2.3.11-stock/README.mpiexec pbs-2.3.11/README.mpiexec
--- pbs-2.3.11-stock/README.mpiexec	Wed Dec 31 19:00:00 1969
+++ pbs-2.3.11/README.mpiexec	Thu Jan 25 10:58:53 2001
@@ -0,0 +1,20 @@
+
+Documentation of changes applied as part of the mpiexec patch.
+http://www.osc.edu/~pw/mpiexec.html
+
+
+1. General bug fixes:
+
+src/lib/Libifl/rpp.c
+Incrcease rpp retry count for possibly congested networks.
+
+src/lib/Libifl/tm.c
+Do not call DIS_tcp_setup(-1) if connection to the local mom failed
+after 5 tries.
+
+2. Functionality additions:
+
+src/resmom/start_exec.c
+Added extension to get stdin/out/err files from the environment rather than
+always using /dev/null during tm_spawn.
+
diff -ruN pbs-2.3.11-stock/src/lib/Libifl/rpp.c pbs-2.3.11/src/lib/Libifl/rpp.c
--- pbs-2.3.11-stock/src/lib/Libifl/rpp.c	Fri Sep 29 17:29:46 2000
+++ pbs-2.3.11/src/lib/Libifl/rpp.c	Thu Dec 28 18:35:02 2000
@@ -186,7 +186,7 @@
 /*
 **	Default number of sendto attempts on a *packet.
 */
-#define	RPP_RETRY	10
+#define	RPP_RETRY	30
 /*
 **	Max allowed number of outstanding pkts
 */
diff -ruN pbs-2.3.11-stock/src/lib/Libifl/tm.c pbs-2.3.11/src/lib/Libifl/tm.c
--- pbs-2.3.11-stock/src/lib/Libifl/tm.c	Thu Jan 25 10:10:54 2001
+++ pbs-2.3.11/src/lib/Libifl/tm.c	Thu Jan 25 10:54:47 2001
@@ -451,7 +451,8 @@
 		}
 
 	}
-	DIS_tcp_setup(local_conn);
+	if (local_conn >= 0)
+	    DIS_tcp_setup(local_conn);
 	return (local_conn);
 }
 
diff -ruN pbs-2.3.11-stock/src/resmom/start_exec.c pbs-2.3.11/src/resmom/start_exec.c
--- pbs-2.3.11-stock/src/resmom/start_exec.c	Thu Jan 25 10:10:55 2001
+++ pbs-2.3.11/src/resmom/start_exec.c	Thu Jan 25 10:01:54 2001
@@ -1389,6 +1389,42 @@
 }
 
 /*
+ * Look for a certain environment variable which has a port# which should
+ * be opened on the MS to establish communication for one of the 3 stdio
+ * streams.  >=0 return is that valid fd, -1 means no env var found,
+ * -2 means malformed env value or failure to connect.
+ */
+static int
+search_env_and_open(const char *envname, u_long ipaddr)
+{
+    static char *id = "search_env_and_open";
+    int i, len = strlen(envname);
+
+    for (i=0; i<vtable.v_used; i++)
+	if (!strncmp(vtable.v_envp[i], envname, len)) {
+	    const char *cp = vtable.v_envp[i] + len;
+	    char *cq;
+	    int fd, port;
+	    if (*cp++ != '=') break;  /* empty, ignore it */
+	    port = strtol(cp, &cq, 10);
+	    if (*cq) {
+		log_err(errno, id, "improper value for MPIEXEC_STD*_PORT");
+		return -2;
+	    }
+#if 0       /* debugging */
+	    log_err(0, "search_env_and_open attempting open", vtable.v_envp[i]);
+#endif
+	    if ((fd = open_demux(ipaddr, port)) < 0) {
+		log_err(errno, id, "failed connect to mpiexec process on MS");
+		log_err(errno, id, vtable.v_envp[i]);
+		return -2;
+	    }
+	    return fd;
+	}
+    return -1;  /* not found */
+}
+
+/*
 ** Start a process for a spawn request.  This will be different from
 ** a job's initial shell task in that the environment will be specified
 ** and no interactive code need be included.
@@ -1407,7 +1443,7 @@
 	int	pipes[2], kid_read, kid_write, parent_read, parent_write;
 	int	pts;
 	int	i, j;
-	int	fd;
+	int	fd0, fd1, fd2;
 	u_long	ipaddr;
 	struct	array_strings	*vstrs;
 	struct  startjob_rtn sjr;
@@ -1631,30 +1667,40 @@
 	/*
 	** Set up stdin.
 	*/
-	if ((fd = open("/dev/null", O_RDONLY)) == -1) {
+	/* look through env for a port# on MS we should use for stdin */
+	if ((fd0 = search_env_and_open("MPIEXEC_STDIN_PORT", ipaddr)) == -2)
+	    starter_return(kid_write, kid_read, JOB_EXEC_FAIL2, &sjr);
+	/* use /dev/null if no env var found */
+	if (fd0 < 0 && (fd0 = open("/dev/null", O_RDONLY)) == -1) {
 		log_err(errno, "newtask", "could not open devnull");
 		(void)close(0);
 	}
 	else {
-		(void)dup2(fd, 0);
-		if (fd > 0)
-			(void)close(fd);
+		(void)dup2(fd0, 0);
+		if (fd0 > 0)
+			(void)close(fd0);
 	}
 
+	/* look through env for a port# on MS we should use for stdout/err */
+	if ((fd1 = search_env_and_open("MPIEXEC_STDOUT_PORT", ipaddr)) == -2)
+	    starter_return(kid_write, kid_read, JOB_EXEC_FAIL2, &sjr);
+	if ((fd2 = search_env_and_open("MPIEXEC_STDERR_PORT", ipaddr)) == -2)
+	    starter_return(kid_write, kid_read, JOB_EXEC_FAIL2, &sjr);
+
 	if (pjob->ji_numnodes > 1) {
 		/*
 		** Open sockets to demux proc for stdout and stderr.
 		*/
-		if ((fd = open_demux(ipaddr, pjob->ji_stdout)) == -1)
+		if (fd1 < 0 && (fd1 = open_demux(ipaddr,pjob->ji_stdout)) == -1)
 		      starter_return(kid_write, kid_read, JOB_EXEC_FAIL2, &sjr);
-		(void)dup2(fd, 1);
-		if (fd > 1)
-			(void)close(fd);
-		if ((fd = open_demux(ipaddr, pjob->ji_stderr)) == -1)
+		(void)dup2(fd1, 1);
+		if (fd1 > 1)
+			(void)close(fd1);
+		if (fd2 < 0 && (fd2 = open_demux(ipaddr,pjob->ji_stderr)) == -1)
 		      starter_return(kid_write, kid_read, JOB_EXEC_FAIL2, &sjr);
-		(void)dup2(fd, 2);
-		if (fd > 2)
-			(void)close(fd);
+		(void)dup2(fd2, 2);
+		if (fd2 > 2)
+			(void)close(fd2);
 	
 		(void)write(1,pjob->ji_wattr[(int)JOB_ATR_Cookie].at_val.at_str,
 		     strlen(pjob->ji_wattr[(int)JOB_ATR_Cookie].at_val.at_str));
@@ -1664,17 +1710,41 @@
 
             (pjob->ji_wattr[(int)JOB_ATR_interactive].at_val.at_long > 0)) {
 		/* interactive job, single node, write to pty */
-		if ((pts = open_pty(pjob)) < 0) {
+		pts = -1;
+		if (fd1 < 0 || fd2 < 0) {
+		    if ((pts = open_pty(pjob)) < 0) {
 			log_err(errno, id,"cannot open slave");
 			starter_return(kid_write, kid_read,JOB_EXEC_FAIL1,&sjr);
+		    }
+		    if (fd1 < 0)
+			fd1 = pts;
+		    if (fd2 < 0)
+			fd2 = pts;
 		}
-		(void)dup2(pts, 1);
-                (void)dup2(pts, 2);
-
+		(void)dup2(fd1, 1);
+		(void)dup2(fd2, 2);
+		if (fd1 != pts)
+		    (void) close(fd1);
+		if (fd2 != pts)
+		    (void) close(fd2);
 	} else {
 		/* normal batch job, single node, write straight to files */
-		if (open_std_out_err(pjob) == -1) {
+		pts = -1;
+		if (fd1 < 0 || fd2 < 0) {
+		    if (open_std_out_err(pjob) == -1)
 			starter_return(kid_write, kid_read,JOB_EXEC_FAIL1,&sjr);
+		}
+		if (fd1 >= 0) {
+		    (void) close(1);
+		    (void) dup2(fd1, 1);
+		    if (fd1 > 1)
+			(void) close(fd1);
+		}
+		if (fd2 >= 0) {
+		    (void) close(2);
+		    (void) dup2(fd2, 2);
+		    if (fd2 > 2)
+			(void) close(fd2);
 		}
 	}