Source Joachim Nilsson:

 Collect forked off children from M-| command

 Mg left zombies from commands executed when piping a region of text to
 an external command.  This patch makes sure to collect for the child
 before returning.

ok sunil@ millert@

1 files changed, 9 insertions, 4 deletions

diff --git a/usr.bin/mg/region.c b/usr.bin/mg/region.c
index 560a608cc91..0a1a75262c9 100644
--- a/usr.bin/mg/region.c
+++ b/usr.bin/mg/region.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: region.c,v 1.35 2015/03/19 21:22:15 bcallah Exp $	*/
+/*	$OpenBSD: region.c,v 1.36 2016/09/08 07:50:09 lum Exp $	*/
 
 /* This file is in the public domain. */
 
@@ -12,6 +12,7 @@
 #include <sys/queue.h>
 #include <sys/socket.h>
 #include <sys/types.h>
+#include <sys/wait.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <poll.h>
@@ -515,8 +516,9 @@ int
 pipeio(const char* const path, char* const argv[], char* const text, int len,
     struct buffer *outbp)
 {
-	int s[2];
+	int s[2], ret;
 	char *err;
+	pid_t pid;
 
 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, s) == -1) {
 		dobeep();
@@ -524,7 +526,7 @@ pipeio(const char* const path, char* const argv[], char* const text, int len,
 		return (FALSE);
 	}
 
-	switch(fork()) {
+	switch((pid = fork())) {
 	case -1:
 		dobeep();
 		ewprintf("Can't fork");
@@ -548,7 +550,10 @@ pipeio(const char* const path, char* const argv[], char* const text, int len,
 	default:
 		/* Parent process */
 		close(s[1]);
-		return (iomux(s[0], text, len, outbp));
+		ret = iomux(s[0], text, len, outbp);
+		waitpid(pid, NULL, 0); /* Collect child to prevent zombies */
+
+		return (ret);
 	}
 	return (FALSE);
 }