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Global Locking Routines
[Apache Portability Runtime library]


Typedefs

typedef apr_global_mutex_t apr_global_mutex_t

Functions

apr_status_t apr_global_mutex_create (apr_global_mutex_t **mutex, const char *fname, apr_lockmech_e mech, apr_pool_t *pool)
apr_status_t apr_global_mutex_child_init (apr_global_mutex_t **mutex, const char *fname, apr_pool_t *pool)
apr_status_t apr_global_mutex_lock (apr_global_mutex_t *mutex)
apr_status_t apr_global_mutex_trylock (apr_global_mutex_t *mutex)
apr_status_t apr_global_mutex_unlock (apr_global_mutex_t *mutex)
apr_status_t apr_global_mutex_destroy (apr_global_mutex_t *mutex)
apr_pool_tapr_global_mutex_pool_get (const apr_global_mutex_t *theglobal_mutex)

Typedef Documentation

typedef struct apr_global_mutex_t apr_global_mutex_t
 

Opaque global mutex structure.


Function Documentation

apr_status_t apr_global_mutex_child_init apr_global_mutex_t **    mutex,
const char *    fname,
apr_pool_t   pool
 

Re-open a mutex in a child process.

Parameters:
mutex  The newly re-opened mutex structure.
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_global_mutex_create().
pool  The pool to operate on.
Remarks:
This function must be called to maintain portability, even if the underlying lock mechanism does not require it.

apr_status_t apr_global_mutex_create apr_global_mutex_t **    mutex,
const char *    fname,
apr_lockmech_e    mech,
apr_pool_t   pool
 

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.

Parameters:
mutex  the memory address where the newly created mutex will be stored.
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_FCNTL
            APR_LOCK_FLOCK
            APR_LOCK_SYSVSEM
            APR_LOCK_POSIXSEM
            APR_LOCK_PROC_PTHREAD
            APR_LOCK_DEFAULT     pick the default mechanism for the platform
 
pool  the pool from which to allocate the mutex.
Warning:
Check APR_HAS_foo_SERIALIZE defines to see if the platform supports APR_LOCK_foo. Only APR_LOCK_DEFAULT is portable.

apr_status_t apr_global_mutex_destroy apr_global_mutex_t   mutex
 

Destroy the mutex and free the memory associated with the lock.

Parameters:
mutex  the mutex to destroy.

apr_status_t apr_global_mutex_lock apr_global_mutex_t   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.

Parameters:
mutex  the mutex on which to acquire the lock.

apr_pool_t* apr_global_mutex_pool_get const apr_global_mutex_t   theglobal_mutex
 

Get the pool used by this global_mutex.

Returns:
apr_pool_t the pool

apr_status_t apr_global_mutex_trylock apr_global_mutex_t   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.

Parameters:
mutex  the mutex on which to attempt the lock acquiring.

apr_status_t apr_global_mutex_unlock apr_global_mutex_t   mutex
 

Release the lock for the given mutex.

Parameters:
mutex  the mutex from which to release the lock.


Generated on Thu Feb 26 22:53:26 2004 for Apache Portable Runtime by doxygen1.2.18