omp_init_nest_lock

 

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Initializes a lock.

Syntax

void omp_init_nest_lock(  
   omp_nest_lock_t *lock  
);  

Remarks

where,

lock
A variable of type omp_nest_lock_t.

Remarks

The initial nesting count is zero.

For more information, see 3.2.1 omp_init_lock and omp_init_nest_lock Functions.

Example

// omp_init_nest_lock.cpp  
// compile with: /openmp  
#include <stdio.h>  
#include <omp.h>  
  
omp_nest_lock_t my_lock;  
  
void Test() {  
   int tid = omp_get_thread_num( );  
   omp_set_nest_lock(&my_lock);  
   printf_s("Thread %d - starting nested locked region\n", tid);  
   printf_s("Thread %d - ending nested locked region\n", tid);  
   omp_unset_nest_lock(&my_lock);  
}  
  
int main() {  
   omp_init_nest_lock(&my_lock);  
  
   #pragma omp parallel num_threads(4)  
   {  
      int i, j;  
  
      for (i = 0; i < 5; ++i) {  
         omp_set_nest_lock(&my_lock);  
            if (i % 3)   
               Test();  
            omp_unset_nest_lock(&my_lock);  
        }  
    }  
  
    omp_destroy_nest_lock(&my_lock);  
}  

Thread 0 - starting nested locked region  
Thread 0 - ending nested locked region  
Thread 0 - starting nested locked region  
Thread 0 - ending nested locked region  
Thread 3 - starting nested locked region  
Thread 3 - ending nested locked region  
Thread 3 - starting nested locked region  
Thread 3 - ending nested locked region  
Thread 3 - starting nested locked region  
Thread 3 - ending nested locked region  
Thread 2 - starting nested locked region  
Thread 2 - ending nested locked region  
Thread 2 - starting nested locked region  
Thread 2 - ending nested locked region  
Thread 2 - starting nested locked region  
Thread 2 - ending nested locked region  
Thread 1 - starting nested locked region  
Thread 1 - ending nested locked region  
Thread 1 - starting nested locked region  
Thread 1 - ending nested locked region  
Thread 1 - starting nested locked region  
Thread 1 - ending nested locked region  
Thread 0 - starting nested locked region  
Thread 0 - ending nested locked region  

See Also

Functions