- do not call pthread_atfork(3) handlers when a multithreaded program

calls vfork(2). "untested, but looks OK" marc@
- document vfork(2), popen(3) and system(3) don't call atfork handlers
in multithreaded programs. okay jmc@

3 files changed, 19 insertions, 6 deletions

diff --git a/lib/libc/gen/popen.3 b/lib/libc/gen/popen.3
index f3ce3b60ca4..df1a8759a6f 100644
--- a/lib/libc/gen/popen.3
+++ b/lib/libc/gen/popen.3
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: popen.3,v 1.15 2007/05/31 19:19:28 jmc Exp $
+.\"	$OpenBSD: popen.3,v 1.16 2008/04/04 19:30:41 kurt Exp $
 .\"
 .\" Copyright (c) 1991, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -27,7 +27,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd $Mdocdate: May 31 2007 $
+.Dd $Mdocdate: April 4 2008 $
 .Dt POPEN 3
 .Os
 .Sh NAME
@@ -94,6 +94,10 @@ the command's standard input is the same as that of the process that called
 Note that
 .Fn popen
 output streams are fully buffered by default.
+In addition, fork handlers established using
+.Xr pthread_atfork 3
+are not called when a multithreaded program calls
+.Fn popen .
 .Pp
 The
 .Fn pclose
diff --git a/lib/libc/stdlib/system.3 b/lib/libc/stdlib/system.3
index 338d3bfa835..a49e595bc0a 100644
--- a/lib/libc/stdlib/system.3
+++ b/lib/libc/stdlib/system.3
@@ -29,9 +29,9 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     $OpenBSD: system.3,v 1.10 2007/05/31 19:19:32 jmc Exp $
+.\"     $OpenBSD: system.3,v 1.11 2008/04/04 19:30:41 kurt Exp $
 .\"
-.Dd $Mdocdate: May 31 2007 $
+.Dd $Mdocdate: April 4 2008 $
 .Dt SYSTEM 3
 .Os
 .Sh NAME
@@ -66,6 +66,11 @@ Otherwise,
 .Fn system
 returns the termination status of the shell in the format specified by
 .Xr waitpid 2 .
+.Pp
+Note that fork handlers established using
+.Xr pthread_atfork 3
+are not called when a multithreaded program calls
+.Fn system .
 .Sh RETURN VALUES
 If a child process cannot be created, or the termination status of
 the shell cannot be obtained,
diff --git a/lib/libc/sys/vfork.2 b/lib/libc/sys/vfork.2
index c1b4b6ec798..ec0e5a75639 100644
--- a/lib/libc/sys/vfork.2
+++ b/lib/libc/sys/vfork.2
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: vfork.2,v 1.15 2007/05/31 19:19:34 jmc Exp $
+.\"	$OpenBSD: vfork.2,v 1.16 2008/04/04 19:30:41 kurt Exp $
 .\"	$NetBSD: vfork.2,v 1.8 1997/07/10 07:54:13 mikel Exp $
 .\"
 .\" Copyright (c) 1980, 1991, 1993
@@ -30,7 +30,7 @@
 .\"
 .\"     @(#)vfork.2	8.1 (Berkeley) 6/4/93
 .\"
-.Dd $Mdocdate: May 31 2007 $
+.Dd $Mdocdate: April 4 2008 $
 .Dt VFORK 2
 .Os
 .Sh NAME
@@ -62,6 +62,10 @@ in that the parent is suspended until the child makes a call to
 or an exit (either by a call to
 .Xr _exit 2
 or abnormally).
+In addition, fork handlers established using
+.Xr pthread_atfork 3
+are not called when a multithreaded program calls
+.Fn vfork .
 .Pp
 .Fn vfork
 returns 0 in the child's context and (later) the PID of the child in