Parallel Programming Guide for HP-UX Systems

Parallel synchronization

Synchronization tools

Chapter 8 139

where (in Fortran)

gate

and

barrier

are gate or barrier variables previously declared in

the gate and barrier allocation functions.

where (in C/C++)

gate_p

and barrier_p are pointers of the indicated type.

NOTE Always free gates and barriers after using them.

Locking functions

The locking functions acquire a gate for exclusive access. If the gate

cannot be immediately acquired, the calling thread waits for it. The

conditional locking functions, which are preﬁxed with COND_ or cond_,

acquire a gate only if a wait is not required. If the gate is acquired, the

functions return 0; if not, they return -1.

The forms of these locking functions are shown in Table 8-4.

C/C++ int free_gate(gate_t *gate_p);

int free_barrier(barrier_t *barrier_p);

Table 8-3 Forms of deallocation functions (Continued)

Language Form

Table 8-4 Forms of locking functions

Language Form

Fortran INTEGER FUNCTION LOCK_GATE(gate)

INTEGER FUNCTION COND_LOCK_GATE(gate)

C/C++ int lock_gate(gate_t *gate_p);

int cond_lock_gate(gate_t *gate_p);