List of OpenMP* Runtime Library Routines

Function

Description

SUBROUTINE omp_set_num_threads(num_threads)

Dynamically set the number of threads to use for this region.

INTEGER FUNCTION omp_get_num_threads()

Determine what the current number of threads is that is permitted to execute a region.

INTEGER FUNCTION omp_get_max_threads()

Obtains the maximum number of threads ever permitted with this OpenMP implementation.

INTEGER FUNCTION omp_get_thread_num()

Determines the unique thread number of the thread currently executing this section of code.

INTEGER FUNCTION omp_get_num_procs()

Determines the number of processors on the current machine.

INTEGER FUNCTION omp_in_parallel()

Determines if the region of code the function is called in is running in parallel. Returns non-zero if inside a parallel region, zero otherwise.

SUBROUTINE omp_set_dynamic(dynamic_threads) INTEGER dynamic_threads

Enable or disable dynamic adjustment of the number of threads used to execute a parallel region. If dynamic_threads is non-zero, dynamic threads are enabled. If dynamic_threads is zero, dynamic threads are disabled.

INTEGER FUNCTION omp_get_dynamic()

Determine whether dynamic adjustment of the number of threads executing a region is supported. Returns non-zero if dynamic adjustment is supported, zero otherwise.

SUBROUTINE omp_set_nested(nested)
INTEGER nested

Enable or disable nested parallelism. If parameter is non-zero, enable. Default is disabled.

INTEGER FUNCTION omp_get_nested()

Determine whether nested parallelism is currently enabled or disabled. Function returns non-zero if nested parallelism is supported, zero otherwise.

SUBROUTINE omp_init_lock(lock) INTEGER lock

Initialize a unique lock and set lock to its value.

SUBROUTINE omp_destroy_lock(lock)
INTEGER lock

 Disassociate lock from any locks.

SUBROUTINE omp_set_lock(lock)
INTEGER lock

Force the executing thread to wait until the lock associated with lock is available. The thread is granted ownership of the lock when it becomes available.

SUBROUTINE omp_unset_lock(lock)
INTEGER lock

Release executing thread from ownership of lock associated with lock. The lock argument must be initialized via omp_init_lock(), and behavior undefined if executing thread does not own the lock associated with lock.

INTEGER omp_test_lock(lock)

Attempt to set lock associated with lock. If successful, return non-zero. lock must be initialized via omp_init_lock(lock).

SUBROUTINE omp_init_nest_lock(lock)
INTEGER lock

 Initialize a unique nested lock and set lock to its value.

SUBROUTINE omp_destroy_nest_lock(lock)
INTEGER lock

Disassociate the nested lock "lock" from any locks.

SUBROUTINE omp_set_nest_lock(lock)
INTEGER lock

Force the executing thread to wait until the lock associated with lock is available. The thread is granted ownership of the lock when it becomes available.

SUBROUTINE omp_unset_nest_lock(lock)
INTEGER lock

Release executing thread from ownership of lock associated with lock if count is zero. lock must be initialized via omp_init_nest_lock(). Behavior is undefined if executing thread does not own the lock associated with lock.

INTEGER omp_test_nest_lock(lock)

Attempt to set lock associated with lock. If successful, return nesting count, otherwise return zero. lock must be initialized via omp_init_lock().