Technical data

#pragma Directives [3]
3.8.8 taskprivate Directive (Cray Standard C Compiler)
The taskprivate directive specifies the task private storage class for variables.
The format of this directive is as follows (the comma-separated list of variables
can be enclosed in parentheses):
#pragma _CRI taskprivate variable,...
Variables that are given a task private storage class are placed in storage so that
each task has a separate copy of the variables; all functions within a task can
access the same copy of the task private variable, but no task can access any task
private variables belonging to another task.
A primary use for task private variables is efficient porting of macrotasked
programs from a shared-memory system (that is, a system, such as VAX, on
which independently executing programs can access the other program’s
memory). On UNICOS and UNICOS/mk systems, independently executing
programs cannot access memory belonging to other programs.
This directive can appear in both global and local scopes and applies only to the
following types of variables:
• Global scope variables, in which case the directive must appear at global
scope.
• Local scope variables with static storage class, in which case the directive
must appear within the same scope as the variable declaration.
When a variable is designated as task private, subsequent declarations of that
variable in the same source file inherit the task private storage class.
The following example, in which each task gets a private copy of x initialized to
10, illustrates the use of the taskprivate directive
main() {
static int x = 10;
#pragma _CRI taskprivate x
...
}
The taskprivate directive takes precedence over the -h common and the
-h taskcommon command line options.
The following restrictions apply to the taskprivate variable:
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