Re: PTHREAD_MUTEX_INITIALIZER


Hallvard B Furuseth wrote:
[...]
Must it be a bug?

No. :-)

"In cases where default mutex attributes are appropriate, the macro
PTHREAD_MUTEX_INITIALIZER can be used to initialize mutexes that are
statically allocated. The effect shall be equivalent to dynamic
initialization by a call to pthread_mutex_init() with parameter attr
specified as NULL, except that no error checks are performed." The thing
is that many programs using PTHREAD_MUTEX_INITIALIZER may well exhibit
undefined behaviour without any application's bugs under the current
wording. It would be helpful if the standard would make it clear that
*initial* call to pthread_mutex_lock() for a PTHREAD_MUTEX_INITIALIZER'd
mutex shall fail for all the same reasons as pthread_mutex_init() (in
addition to the current pthread_mutex_lock() "shall fail" failure
modes)...

regards,
alexander.
.

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