SyncSemaphore::__construct
Constructs a new SyncSemaphore object
Description
public SyncSemaphore::__construct(string $name = ?, int $initialval = 1, bool $autounlock = true)
Parameters
-
name
-
The name of the semaphore if this is a named semaphore object.
Note:
If the name already exists, it must be able to be opened by the current user
that the process is running as or an exception will be thrown with a meaningless
error message.
-
initialval
-
The initial value of the semaphore. This is the number of locks that may be obtained.
-
autounlock
-
Specifies whether or not to automatically unlock the semaphore at the
conclusion of the PHP script.
Warning
If an object is: A named semaphore with an autounlock of false, the object is
locked, and the PHP script concludes before the object is unlocked, then the
underlying semaphore will end up in an inconsistent state.
Return Values
The new SyncSemaphore object.
Errors/Exceptions
An exception is thrown if the semaphore cannot be created or opened.
Examples
Example #1 SyncSemaphore::__construct example
<?php
$semaphore = new SyncSemaphore("LimitedResource_2clients", 2);
if (!$semaphore->lock(3000))
{
echo "Unable to lock semaphore.";
exit();
}
/* ... */
$semaphore->unlock();
?>
See Also
- SyncSemaphore::lock
- SyncSemaphore::unlock