single
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Lets you specify that a section of code should be executed on a single thread, not necessarily the master thread.
Syntax
#pragma omp single [clauses]
{
code_block
}
Parameters
clause (optional)
Zero or more clauses. See the Remarks section for a list of the clauses supported by single.
Remarks
The single directive supports the following OpenMP clauses:
The master directive lets you specify that a section of code should be executed only on the master thread.
For more information, see 2.4.3 single Construct.
Example
// omp_single.cpp
// compile with: /openmp
#include <stdio.h>
#include <omp.h>
int main() {
#pragma omp parallel num_threads(2)
{
#pragma omp single
// Only a single thread can read the input.
printf_s("read input\n");
// Multiple threads in the team compute the results.
printf_s("compute results\n");
#pragma omp single
// Only a single thread can write the output.
printf_s("write output\n");
}
}
read input
compute results
compute results
write output