Home · All Classes · Main Classes · Grouped Classes · Modules · Functions |
The QWriteLocker class is a convenience class that simplifies locking and unlocking read-write locks for write access. More...
#include <QWriteLocker>
Note: All the functions in this class are thread-safe.
The QWriteLocker class is a convenience class that simplifies locking and unlocking read-write locks for write access.
The purpose of QWriteLocker (and QReadLocker is to simplify QReadWriteLock locking and unlocking. Locking and unlocking statements or in exception handling code is error-prone and difficult to debug. QWriteLocker can be used in such situations to ensure that the state of the lock is always well-defined.
Here's an example that uses QWriteLocker to lock and unlock a read-write lock for writing:
QReadWriteLock lock; void writeData(const QByteArray &data) { QWriteLocker locker(&lock); ... }
It is equivalent to the following code:
QReadWriteLock lock; void writeData(const QByteArray &data) { locker.lockForWrite(); ... locker.unlock(); }
The QMutexLocker documentation shows examples where the use of a locker object greatly simplifies programming.
See also QReadLocker and QReadWriteLock.
Constructs a QWriteLocker and locks lock for writing. The lock will be unlocked when the QWriteLocker is destroyed. If lock is zero, QWriteLocker does nothing.
See also QReadWriteLock::lockForWrite().
Destroys the QWriteLocker and unlocks the lock that was passed to the constructor.
See also QReadWriteLock::unlock().
Returns a pointer to the read-write lock that was passed to the constructor.
Relocks an unlocked lock.
See also unlock().
Unlocks the lock associated with this locker.
See also QReadWriteLock::unlock().
Copyright © 2005 Trolltech | Trademarks | Qt 4.1.0 |