Developing and Porting C and C++ Applications on AIX

9.8. Data environment: The threadprivate directive

The threadprivate directive is provided to make file-scope, namespace-scope, or static block-scope variables local to a thread. The syntax of the threadprivate directive is as follows:

#pragma omp threadprivate(variable-list) new-line

Each copy of a threadprivate variable is initialized once, at an unspecified point in the program prior to the first reference to that copy, and in the usual manner (that is, as the master copy would be initialized in a serial execution of the program).

As with any private variable, a thread must not reference another thread’s copy of a threadprivate object. During serial regions and master regions of the program, references will be to the master thread’s copy ...