QNX Developer Support
Attempt to acquire a shared lock on a read-write lock
#include <pthread.h> int pthread_rwlock_tryrdlock( pthread_rwlock_t* rwl );
- A pointer to a pthread_rwlock_t object that you want to lock for reading.
Use the -l c option to qcc to link against this library. This library is usually included automatically.
The pthread_rwlock_tryrdlock() function attempts to acquire a shared lock on the read-write lock referenced by rwl. If the read-write lock is already exclusively locked by any thread (including the calling thread), the function returns immediately instead of blocking until a read lock can be obtained.
- On the first use of a statically initialized read-write lock, insufficient system resources existed to initialize the read-write lock.
- The read-write lock was already write locked.
- The calling thread already has an exclusive lock for rwl.
- A fault occurred when the kernel tried to access rwl.
- The read-write lock rwl is invalid.