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-rw-r--r--linuxthreads/ChangeLog6
-rw-r--r--linuxthreads/linuxthreads.texi11
-rw-r--r--linuxthreads/man/pthread_atfork.man13
3 files changed, 14 insertions, 16 deletions
diff --git a/linuxthreads/ChangeLog b/linuxthreads/ChangeLog
index a926600e85..2b55b8fcfb 100644
--- a/linuxthreads/ChangeLog
+++ b/linuxthreads/ChangeLog
@@ -1,3 +1,9 @@
+2001-12-14  Ulrich Drepper  <drepper@redhat.com>
+
+	* man/pthread_atfork.man: Adjust description of mutex handling
+	after fork for current implementation.
+	* linuxthreads.texi: Likewise [PR libc/2519].
+
 2001-12-13  Andreas Schwab  <schwab@suse.de>
 
 	* specific.c (pthread_key_delete): Don't contact the thread
diff --git a/linuxthreads/linuxthreads.texi b/linuxthreads/linuxthreads.texi
index 9513a67a6a..b4d83c9dee 100644
--- a/linuxthreads/linuxthreads.texi
+++ b/linuxthreads/linuxthreads.texi
@@ -1395,12 +1395,10 @@ pocess image.
 To understand the purpose of @code{pthread_atfork}, recall that
 @code{fork} duplicates the whole memory space, including mutexes in
 their current locking state, but only the calling thread: other threads
-are not running in the child process. Thus, if a mutex is locked by a
-thread other than the thread calling @code{fork}, that mutex will remain
-locked forever in the child process, possibly blocking the execution of
-the child process. Or if some shared data, such as a linked list, was in the
-middle of being updated by a thread in the parent process, the child
-will get a copy of the incompletely updated data which it cannot use.
+are not running in the child process.  The mutexes are not usable after
+the @code{fork} and must be initialized with @code{pthread_mutex_init}
+in the child process.  This is a limitation of the current
+implementation and might or might not be present in future versions.
 
 To avoid this, install handlers with @code{pthread_atfork} as follows: have the
 @var{prepare} handler lock the mutexes (in locking order), and the
@@ -1627,4 +1625,3 @@ of a mapping of user threads to kernel threads.  It exists for source
 compatibility.  However, it will return the value that was set by the
 last call to @code{pthread_setconcurrency}.
 @end deftypefun
-
diff --git a/linuxthreads/man/pthread_atfork.man b/linuxthreads/man/pthread_atfork.man
index 4d06a56f8b..b682bed3ac 100644
--- a/linuxthreads/man/pthread_atfork.man
+++ b/linuxthreads/man/pthread_atfork.man
@@ -30,15 +30,10 @@ while the |parent| and |child| handlers are called in FIFO order
 To understand the purpose of !pthread_atfork!, recall that !fork!(2)
 duplicates the whole memory space, including mutexes in their current
 locking state, but only the calling thread: other threads are not
-running in the child process. Thus, if a mutex is locked by a thread
-other than the thread calling !fork!, that mutex will remain locked
-forever in the child process, possibly blocking the execution of the
-child process. To avoid this, install handlers with !pthread_atfork!
-as follows: the |prepare| handler locks the global mutexes (in locking
-order), and the |parent| and |child| handlers unlock them (in
-reverse order). Alternatively, |prepare| and |parent| can be set to
-!NULL! and |child| to a function that calls !pthread_mutex_init! on
-the global mutexes.
+running in the child process.  The mutexes are not usable after the
+!fork! and must be initialized with |pthread_mutex_init| in the child
+process.  This is a limitation of the current implementation and might
+or might not be present in future versions.
 
 .SH "RETURN VALUE"