From 1952eb50107c76b4d13ebaed85c29e927fb51a61 Mon Sep 17 00:00:00 2001
From: Gustavo Niemeyer <gustavo@niemeyer.net>
Date: Mon, 29 Aug 2011 10:45:37 -0400
Subject: [PATCH] os: fix WNOHANG Waitmsg

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/4962042
---
 src/pkg/os/exec_unix.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/pkg/os/exec_unix.go b/src/pkg/os/exec_unix.go
index 8a4b2e1b806..41e77230ad5 100644
--- a/src/pkg/os/exec_unix.go
+++ b/src/pkg/os/exec_unix.go
@@ -38,7 +38,8 @@ func (p *Process) Wait(options int) (w *Waitmsg, err Error) {
 	if e != 0 {
 		return nil, NewSyscallError("wait", e)
 	}
-	if options&WSTOPPED == 0 {
+	// With WNOHANG pid is 0 if child has not exited.
+	if pid1 != 0 && options&WSTOPPED == 0 {
 		p.done = true
 	}
 	w = new(Waitmsg)