AcquireWriter
status_t status = locker.AcquireWriter(dontBlock, 0);
status_t AcquireWriter(bool dontBlock,
status = locker.AcquireWriter(dontBlock, bytesNeeded);
status_t status = locker.AcquireWriter(dontBlock, 0);
status = locker.AcquireWriter(dontBlock, bytesNeeded);
status_t status = writeLocker.AcquireWriter(0, 1);