Regarding bug 101323, we're seeing either crashes or hangs,
 on occasion, when our multi-threaded process nanny does a
 fork+exec sequence.  We are using FreeBSD 7.2 and libthr
 
 We are super careful with signal masks,
 and do the bare minimum between fork and exec.  However, due
 to various libraries that we use, we have a bunch of threads
 running in the main process.  We've been using this code 
 on 4.6.2 and uniprocessors for years w/out issue.
 We are using 7.2 on 64-bit multi-core platforms. We do:
 
         m_pid = fork();
         if (m_pid == 0 {
            /* pseudo code */
            fstat() and close() file descriptors 3 and above
            setuid() if necessary
            restore signal masks
            setpgid()
            creat() a log file and dup to stdout and stderr
            execve()
         }
 
 Is this approach doomed to failure, or should we be able to get
 this working?  It doesn't look like Daniel's patch is in our
 libthr/thread/thr_fork.c
 So, I can do the obvious and try that.  I'm curious about just
 running __sys_fork() instead, however, as the process is
 going to obliterate itself with execve() anyway.
 
 --
 Brent Welch
 Director, Software Architecture, Panasas Inc
 The Leader in Parallel Storage
 
 www.panasas.com
 welch@panasas.com