copyprivate

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Specifies that one or more variables should be shared among all threads.

Syntax

copyprivate
(var)  

Remarks

where,

var
One or more variables to share. If more than one variable is specified, separate variable names with a comma.

Remarks

copyprivate applies to the single directive.

For more information, see 2.7.2.8 copyprivate.

Example

// omp_copyprivate.cpp  
// compile with: /openmp   
#include <stdio.h>  
#include <omp.h>  
  
float x, y, fGlobal = 1.0;  
#pragma omp threadprivate(x, y)  
  
float get_float() {  
   fGlobal += 0.001;  
   return fGlobal;  
}  
  
void use_float(float f, int t) {  
   printf_s("Value = %f, thread = %d\n", f, t);  
}  
  
void CopyPrivate(float a, float b) {  
   #pragma omp single copyprivate(a, b, x, y)   
   {  
      a = get_float();  
      b = get_float();  
      x = get_float();  
      y = get_float();  
    }  
  
   use_float(a, omp_get_thread_num());     
   use_float(b, omp_get_thread_num());     
   use_float(x, omp_get_thread_num());  
   use_float(y, omp_get_thread_num());  
}  
  
int main() {  
   float a = 9.99, b = 123.456;  
  
   printf_s("call CopyPrivate from a single thread\n");  
   CopyPrivate(9.99, 123.456);  
  
   printf_s("call CopyPrivate from a parallel region\n");  
   #pragma omp parallel       
   {  
      CopyPrivate(a, b);  
   }  
}  

call CopyPrivate from a single thread  
Value = 1.001000, thread = 0  
Value = 1.002000, thread = 0  
Value = 1.003000, thread = 0  
Value = 1.004000, thread = 0  
call CopyPrivate from a parallel region  
Value = 1.005000, thread = 0  
Value = 1.005000, thread = 1  
Value = 1.006000, thread = 0  
Value = 1.006000, thread = 1  
Value = 1.007000, thread = 0  
Value = 1.007000, thread = 1  
Value = 1.008000, thread = 0  
Value = 1.008000, thread = 1  

See Also

Clauses