svn commit: r273644 - head/share/man/man3

[John Baldwin]

Author: jhb
Date: Sat Oct 25 19:31:34 2014
New Revision: 273644
URL: https://svnweb.freebsd.org/changeset/base/273644

Log:
  Clarify that pthread_cleanup_push()/pop() are implemented as macros that
  create a new code block and thus must be balanced at the same lexical
  scope.  (This is also a requirement in POSIX.)
  
  PR:		194280
  Submitted by:	dr2867.business at pacbell.net
  MFC after:	1 week

Modified:
  head/share/man/man3/pthread_cleanup_pop.3
  head/share/man/man3/pthread_cleanup_push.3

Modified: head/share/man/man3/pthread_cleanup_pop.3
==============================================================================
--- head/share/man/man3/pthread_cleanup_pop.3	Sat Oct 25 19:01:02 2014	(r273643)
+++ head/share/man/man3/pthread_cleanup_pop.3	Sat Oct 25 19:31:34 2014	(r273644)
@@ -27,7 +27,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 30, 1998
+.Dd October 25, 2014
 .Dt PTHREAD_CLEANUP_POP 3
 .Os
 .Sh NAME
@@ -50,6 +50,14 @@ If there is no cleanup routine
 then
 .Fn pthread_cleanup_pop
 does nothing.
+.Pp
+The
+.Fn pthread_cleanup_push
+function is implemented as a macro that closes a block.
+Invocations of this function must appear as standalone statements that are
+paired with an earlier call of
+.Xr pthread_cleanup_push 3
+in the same lexical scope.
 .Sh RETURN VALUES
 The
 .Fn pthread_cleanup_pop

Modified: head/share/man/man3/pthread_cleanup_push.3
==============================================================================
--- head/share/man/man3/pthread_cleanup_push.3	Sat Oct 25 19:01:02 2014	(r273643)
+++ head/share/man/man3/pthread_cleanup_push.3	Sat Oct 25 19:31:34 2014	(r273644)
@@ -27,7 +27,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 30, 1998
+.Dd October 25, 2014
 .Dt PTHREAD_CLEANUP_PUSH 3
 .Os
 .Sh NAME
@@ -52,6 +52,14 @@ When
 is called, it is passed
 .Fa arg
 as its only argument.
+.Pp
+The
+.Fn pthread_cleanup_push
+function is implemented as a macro that opens a new block.
+Invocations of this function must appear as standalone statements that are
+paired with a later call of
+.Xr pthread_cleanup_pop 3
+in the same lexical scope.
 .Sh RETURN VALUES
 The
 .Fn pthread_cleanup_push