From 100541ec40cecbc5963dbaa513ce8801836b995e Mon Sep 17 00:00:00 2001
From: Ingo Weinhold <ingo_weinhold@gmx.de>
Date: Wed, 15 Jun 2011 02:42:53 +0000
Subject: [PATCH] waitpid(): Fixed regression introduced with my signals
 changes: When WNOHANG was specified the syscall error code B_WOULD_BLOCK
 would no longer be mapped to 0. Fixes #7693.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@42188 a95241bf-73f2-0310-859d-f6bbb57e9c96
---
 src/system/libroot/posix/sys/wait.cpp | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/system/libroot/posix/sys/wait.cpp b/src/system/libroot/posix/sys/wait.cpp
index 05fe759a1b..ce4beedf9f 100644
--- a/src/system/libroot/posix/sys/wait.cpp
+++ b/src/system/libroot/posix/sys/wait.cpp
@@ -32,8 +32,13 @@ waitpid(pid_t pid, int* _status, int options)
 
 	pthread_testcancel();
 
-	if (child < 0)
+	if (child < 0) {
+		// When not getting a child status when WNOHANG was specified, don't
+		// fail.
+		if (child == B_WOULD_BLOCK && (options & WNOHANG) != 0)
+			return 0;
 		RETURN_AND_SET_ERRNO(child);
+	}
 
 	// prepare the status
 	if (_status != NULL) {