From cdcaddfc079757aeedfc03b412cf0b74b5132831 Mon Sep 17 00:00:00 2001
From: Michael Kerrisk <mtk.manpages@gmail.com>
Date: Sun, 17 Sep 2006 06:21:29 +0000
Subject: [PATCH] Noted interactions with fork handlers in multithreaded
 programs.

---
 man2/vfork.2 | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/man2/vfork.2 b/man2/vfork.2
index 66edd97dd..7e72a9c0e 100644
--- a/man2/vfork.2
+++ b/man2/vfork.2
@@ -170,6 +170,17 @@ or
 .BR _exit ()
 and cannot rely on any specific behaviour w.r.t. shared memory.
 .\" In AIXv3.1 vfork is equivalent to fork.
+.SH "LINUX NOTES"
+Fork handlers established using
+.BR pthread_atfork (3)
+are not called when a multithreaded program employing 
+the NPTL threading library calls
+.BR vfork ().
+Fork handlers are called in this case in a program using the 
+LinuxThreads threading library.
+(See
+.BR pthreads (7)
+for a description of Linux threading libraries.)
 .SH "SEE ALSO"
 .BR clone (2),
 .BR execve (2),