From owner-freebsd-hackers@FreeBSD.ORG  Tue Jun 22 14:57:17 2004
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Date: Tue, 22 Jun 2004 09:56:33 -0500
From: Dan Nelson <dnelson@allantgroup.com>
To: Chris Stenton <jacs@gnome.co.uk>
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Subject: Re: pthread - fork - execv problem
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In the last episode (Jun 21), Chris Stenton said:
> I am trying to help port over an app thats posix threaded. One thread
> uses fork, dup2 and execv to start a child programme in this case an
> mp3 player. However, under FreeBSD-5.2.1, the execv causes all the
> threads in the parent process to be blocked until the child process
> returns. Is there a mechanism to get around this.

Do you have a small testcase?  I have not seen your problem in any
other threaded programs on FreeBSD.

It may be an application bug.  After a fork both processes are
independant.  The child should not be able to affect the parent like
this, unless the parent does something like holding a mutex used by all
the threads and calling wait().

-- 
	Dan Nelson
	dnelson@allantgroup.com