cpp/thread/shared lock/try lock

Tries to lock the associated mutex in shared mode without blocking. Effectively calls.

std is thrown if there is no associated mutex or if the mutex is already locked.

Parameters
(none)

Return value
if the ownership of the mutex has been acquired successfully, otherwise.

Exceptions

 * Any exceptions thrown by


 * If there is no associated mutex, std with an error code of std


 * If the mutex is already locked, std with an error code of std