- Mladen Turk
- $Revision: 515 $, $Date: 2008-03-17 22:02:23 +0100 (Mon, 17 Mar 2008) $
Create and initialize a mutex that can be used to synchronize both
processes and threads. Note: There is considerable overhead in using
this API if only cross-process or cross-thread mutual exclusion is
required. See apr_proc_mutex.h and apr_thread_mutex.h for more
specialized lock routines.
Check APR_HAS_foo_SERIALIZE defines to see if the platform supports
APR_LOCK_foo. Only APR_LOCK_DEFAULT is portable.
fname A file name to use if the lock mechanism requires one. This
argument should always be provided. The lock code itself will
determine if it should be used.
mech The mechanism to use for the interprocess lock, if any; one of
APR_LOCK_DEFAULT pick the default mechanism for the platform
pool the pool from which to allocate the mutex.
- Newly created mutex.
public static native long create(String fname, int mech, long pool)
Re-open a mutex in a child process.
fname A file name to use if the mutex mechanism requires one. This
argument should always be provided. The mutex code itself will
determine if it should be used. This filename should be the
same one that was passed to apr_proc_mutex_create().
pool The pool to operate on.
This function must be called to maintain portability, even
if the underlying lock mechanism does not require it.
- Newly opened mutex.
Acquire the lock for the given mutex. If the mutex is already locked,
the current thread will be put to sleep until the lock becomes available.
mutex the mutex on which to acquire the lock.
public static native int lock(long mutex);
Attempt to acquire the lock for the given mutex. If the mutex has already
been acquired, the call returns immediately with APR_EBUSY. Note: it
is important that the APR_STATUS_IS_EBUSY(s) macro be used to determine
if the return value was APR_EBUSY, for portability reasons.
mutex the mutex on which to attempt the lock acquiring.
public static native int trylock(long mutex);
Release the lock for the given mutex.
mutex the mutex from which to release the lock.
public static native int unlock(long mutex);
Destroy the mutex and free the memory associated with the lock.
mutex the mutex to destroy.
public static native int destroy(long mutex);