Add a manpage for pthread_atfork(3). This copies a lot of the text of

the Open Group manpage for pthread_atfork(), available online at:

http://www.opengroup.org/onlinepubs/009695399/functions/pthread_atfork.html

which should be ok, since Daniel Eischen had mailed me about Open
Group manpages and the fact that they have granted permission to
FreeBSD to use their material.  Any differences from the OG text are
my changes to the original manpage text submitted by Alex Vasylenko:

- In an effort to clean up the part that describes hooks and their
  calling order, I used a list instead of a single paragraph for all the three
  types of fork() hooks.
- After a short discussion with Dima Dorfman a long long time ago in a
  far away galaxy, I changed the RETURN VALUES section to look more
  like the rest of the pthread_xxx.3 manpages.

PR:		docs/68201
Submitted by:	Alex Vasylenko <lxv@omut.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/share/man/man3/pthread.3 b/share/man/man3/pthread.3
index 076aefe..5ebb88d 100644
--- a/share/man/man3/pthread.3
+++ b/share/man/man3/pthread.3
@@ -447,6 +447,15 @@ Set the thread-specific value for the specified key.
 .Ss Cleanup Routines
 .Bl -tag -width indent
 .It Xo
+.Ft int
+.Fo pthread_atfork
+.Fa "void \*[lp]*prepare\*[rp]\*[lp]void\*[rp]"
+.Fa "void \*[lp]*parent\*[rp]\*[lp]void\*[rp]"
+.Fa "void \*[lp]*child\*[rp]\*[lp]void\*[rp]"
+.Fc
+.Xc
+Register fork handlers
+.It Xo
 .Ft void
 .Fn pthread_cleanup_pop "int execute"
 .Xc
@@ -472,6 +481,7 @@ They contain both thread-safe versions of
 functions and the thread functions.
 Threaded applications are linked with one of these libraries.
 .Sh SEE ALSO
+.Xr pthread_atfork 3 ,
 .Xr pthread_cleanup_pop 3 ,
 .Xr pthread_cleanup_push 3 ,
 .Xr pthread_condattr_destroy 3 ,