cpp/thread/shared lock

The class is a general-purpose shared mutex ownership wrapper allowing deferred locking, timed locking and transfer of lock ownership. Locking a locks the associated shared mutex in shared mode (to lock it in exclusive mode, std can be used).

The class is movable, but not copyable – it meets the requirements of  and  but not of  or.

meets the requirements. If meets the  requirements,  also meets  requirements.

In order to wait in a shared mutex in shared ownership mode, std can be used (std requires std and so can only wait in unique ownership mode).