[Asterisk-bsd] Real usefullness of mpg123 dependency / rxfax note

[Luigi Rizzo]

On Thu, Feb 23, 2006 at 01:05:41PM -0600, Dr. Rich Murphey wrote:
...
> If you see mpg123 consume 100% CPU upon
> shutting down asterisk, this sounds like a
> familiar symptom.
> I recall looking at mpg123 and finding that
> when asterisk exits and closes the pipe to
> mpg123, mpg123 would not detect
> that the pipe closed, but rather loop indefinitely
> reading 0 bytes from the closed pipe.
> 
> Since it's possible for the pipe to close unexpectedly
> I assumed that this was a bug in mpg123.

this is one part, but there was more to this.

At least on freebsd 4.11 (with libc_r)
there is also a problem when asterisk forks an
external processes and then exec()s a new one, because of
the way the low-numbered io descriptor are handled
(libc_r wants them non-blocking, but since they are shared,
the other program could change them into blocking mode,
which screws up the userland threading library).

The description i posted at the time is here

http://archives.vault9.net/arc/mailing/freebsd-hackers/0218.html

	cheers
	luigi