--- ray/src/common/unix_process.c	2003/11/10 16:41:52	3.3
+++ ray/src/common/unix_process.c	2016/03/04 02:48:14	3.11
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char	RCSid[] = "$Id: unix_process.c,v 3.3 2003/11/10 16:41:52 greg Exp $";
+static const char	RCSid[] = "$Id: unix_process.c,v 3.11 2016/03/04 02:48:14 greg Exp $";
 #endif
 /*
  * Routines to communicate with separate process via dual pipes
@@ -12,8 +12,11 @@ static const char	RCSid[] = "$Id: unix_process.c,v 3.3
 
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <fcntl.h>
+#include <stdlib.h>
 
 #include "rtprocess.h"
+#include "rtio.h"
 
 
 int
@@ -22,18 +25,19 @@ SUBPROC *pd,
 char	*av[]
 )
 {
-	extern char	*getpath(), *getenv();
 	char	*compath;
 	int	p0[2], p1[2];
 
-	pd->running = 0; /* not yet */
-					/* find executable */
-	compath = getpath(av[0], getenv("PATH"), 1);
-	if (compath == 0)
+	pd->pid = 0;
+	pd->running = 0;		/* not going yet */
+	
+	if (av == NULL)			/* cloning operation? */
+		compath = NULL;
+	else if ((compath = getpath(av[0], getenv("PATH"), X_OK)) == NULL)
 		return(0);
 	if (pipe(p0) < 0 || pipe(p1) < 0)
 		return(-1);
-	if ((pd->pid = vfork()) == 0) {		/* if child */
+	if ((pd->pid = fork()) == 0) {	/* if child... */
 		close(p0[1]);
 		close(p1[0]);
 		if (p0[0] != 0) {	/* connect p0 to stdin */
@@ -44,7 +48,9 @@ char	*av[]
 			dup2(p1[1], 1);
 			close(p1[1]);
 		}
-		execv(compath, av);	/* exec command */
+		if (compath == NULL)	/* just cloning? */
+			return(0);
+		execv(compath, av);	/* else exec command */
 		perror(compath);
 		_exit(127);
 	}
@@ -54,26 +60,56 @@ char	*av[]
 	close(p1[1]);
 	pd->r = p1[0];
 	pd->w = p0[1];
+	/*
+	 * Close write stream on exec to avoid multiprocessing deadlock.
+	 * No use in read stream without it, so set flag there as well.
+	 * GW: This bug took me two days to figure out!!
+	 */
+	fcntl(pd->r, F_SETFD, FD_CLOEXEC);
+	fcntl(pd->w, F_SETFD, FD_CLOEXEC);
 	pd->running = 1;
 	return(PIPE_BUF);
 }
 
 
-
 int
-close_process(		/* close pipes and wait for process */
-SUBPROC *pd
+close_processes(	/* close pipes and wait for processes to finish */
+SUBPROC pd[],
+int nproc
 )
 {
-	int	pid, status;
+	int	togo = nproc;
+	int	status, rtn_status = 0;
+	RT_PID	pid;
+	int	i;
 
-	close(pd->r);
-	close(pd->w);
-	pd->running = 0;
-	while ((pid = wait(&status)) != -1)
-		if (pid == pd->pid)
-			return(status>>8 & 0xff);
-	return(-1);		/* ? unknown status */
+	for (i = 0; i < nproc; i++)		/* close pipes, first */
+		if (pd[i].running) {
+			close(pd[i].w);
+			close(pd[i].r);
+			pd[i].running = 0;
+		}
+	if (nproc == 1) {			/* await specific process? */
+		if (waitpid(pd->pid, &status, 0) != pd->pid)
+			return(-1);
+		pd->pid = 0;
+		return(status>>8 & 0xff);
+	}
+						/* else unordered wait */
+	while (togo > 0 && (pid = wait(&status)) >= 0) {
+		for (i = nproc; i-- > 0; )
+			if (pd[i].pid == pid) {
+				pd[i].pid = 0;
+				--togo;
+				break;
+			}
+		if (i < 0)
+			continue;		/* child we don't know? */
+		status = status>>8 & 0xff;
+		if (status)			/* record non-zero status */
+			rtn_status = status;
+	}
+	if (togo)				/* child went missing? */
+		return(-1);
+	return(rtn_status);
 }
-
-