Attempt to lock this readers-writer mutex for reading.
Declared in <bslmt_rwmutex.h>
int
tryLockRead();Immediately return 0 on success, and a non-zero value if there are active or pending writers. If successful, unlock must be used to release the lock on this mutex. The behavior is undefined if this method is called from a thread that already has a lock on this mutex.
0 on success, and a non-zero value if there are active or pending writers