streamWrapper::stream_lock

(PHP 5, PHP 7, PHP 8)

streamWrapper::stream_lock — Advisory file locking

Description

This method is called in response to flock() , when file_put_contents() (when flags contains LOCK_EX ), stream_set_blocking() and when closing the stream (LOCK_UN ).

Parameters

operation

operation is one of the following:

• LOCK_SH to acquire a shared lock (reader).
• LOCK_EX to acquire an exclusive lock (writer).
• LOCK_UN to release a lock (shared or exclusive).
• LOCK_NB if you don't want flock() to block while locking. (not supported on Windows)

Return Values

Returns true on success or false on failure.

Errors/Exceptions

Emits E_WARNING if call to this method fails (i.e. not implemented).

See Also

• stream_set_blocking() - Set blocking/non-blocking mode on a stream
• flock() - Portable advisory file locking