ssh2: from steve stallion.  The exit-status request message is needed to script externally.

Reference: /n/atom/patch/applied2013/ssh2exit
Date: Fri Sep 27 21:27:35 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/ssh2/sshtun.c	Fri Sep 27 21:27:35 2013
+++ /sys/src/cmd/ssh2/sshtun.c	Fri Sep 27 21:27:35 2013
@@ -1308,6 +1308,13 @@
 		add_string(p, cmd);
 		free(cmd);
 	}
+	else if (strcmp(toks[0], "exit-status") == 0) {
+		add_byte(p, SSH_MSG_CHANNEL_REQUEST);
+		add_uint32(p, ch->otherid);
+		add_string(p, "exit-status");
+		add_byte(p, 0);
+		add_uint32(p, atoi(toks[1]));	/* exit_status */
+	}
 	else {
 		r->aux = 0;
 		respond(r, "invalid request command");
--- /sys/src/cmd/ssh2/sshsession.c	Fri Sep 27 21:27:35 2013
+++ /sys/src/cmd/ssh2/sshsession.c	Fri Sep 27 21:27:35 2013
@@ -381,7 +381,8 @@
 runcmd(int reqfd, int datafd, char *svc, char *cmd, char *arg1, char *arg2)
 {
 	char *p;
-	int fd, cmdpid, child;
+	int fd, cmdpid;
+	Waitmsg *w;
 
 	cmdpid = rfork(RFPROC|RFMEM|RFNOTEG|RFFDG);
 	switch (cmdpid) {
@@ -413,13 +414,17 @@
 		close(datafd);
 		while (1) {
 			fprint(errfd, "waiting for child %d\n", cmdpid);
-			child = waitpid();
-			fprint(errfd, "child %d passed\n", child);
-			if (child == cmdpid || child == -1)
+			w = wait();
+			fprint(errfd, "child %d passed\n", w->pid);
+			if (w->pid == cmdpid || w->pid == -1)
 				break;
+			free(w);
 		}
-		if (child == -1)
+		if (w->pid == -1)
 			fprint(errfd, "wait failed: %r\n");
+		else
+			fprint(reqfd, "exit-status %d", w->msg[0]);
+		free(w);
 		if (slfd > 0)
 			fprint(slfd, "closing ssh session for %s\n", uname);
 		else