Re: [patch] Fix shared_timed_mutex::try_lock_until() et al

[Jonathan Wakely <jwakely@redhat.com>]

On 10/04/15 11:56 +0200, Torvald Riegel wrote:
>Ah, right.  I was confused by the name, thinking those targets don't
>support pthread_mutex_timedlock, not pthread_rwlock_timedrdlock etc.

The macro actually relates to the _POSIX_TIMEOUTS macro, but was
originally added to check for pthread_mutex_timedlock support, hence
its name. Maybe a better name would be _GLIBCXX_USE_MUTEX_TIMEOUTS.

Both pthread_mutex_timedlock and pthread_rwlock_timed??lock were
originally part of the POSIX Timeouts option, so on older POSIX
systems they are only available when _POSIX_TIMEOUTS is defined.
(They are part of the base spec in the current POSIX standard, but
Darwin and HPUX don't implement that and still treat them as
optional.)