[PATCH] Fix return value and errno set by sem_init(), sem_destroy() and sem_close()

Christopher Faylor cgf-use-the-mailinglist-please@cygwin.com
Mon Mar 28 22:17:00 GMT 2011

On Mon, Mar 28, 2011 at 11:14:03PM +0100, Jon TURNEY wrote:
>While looking into some mysterious failures of sem_init() in python, I was
>somewhat surprised to find the following comment in python/thread_pthread.h:
>> /*
>>  * As of February 2002, Cygwin thread implementations mistakenly report error
>>  * codes in the return value of the sem_ calls (like the pthread_ functions).
>>  * Correct implementations return -1 and put the code in errno. This supports
>>  * either.
>>  */
>While this comment refers to sem_wait() and sem_trywait(), which seem to have
>been fixed since [1], it seems that sem_init(), sem_destroy() and sem_close()
>are still non-conformant with SUS in that (i) they do not set errno, and (ii)
>they don't return -1 on failure, instead returning the value which should be
>set as errno.
>2011-03-28  Jon TURNEY  <jon.turney@dronecode.org.uk>
>	* thread.cc (semaphore::init, destroy, close): Standards conformance
>	fix.  On a failure, return -1 and set errno.
>	* thread.h (semaphore::terminate): Save errno since semaphore::close()
>	may now modify it.
>[1] http://cygwin.com/ml/cygwin/2002-02/msg01379.html

Looks good.  Please check in ASAP so this will make it into 1.7.9.



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