# NAG Library Routine Document

## 1Purpose

x06xaf returns $1$ when using a multi-threaded implementation of the NAG Library and $0$ otherwise.

## 2Specification

Fortran Interface
 Function x06xaf ( )
 Integer :: x06xaf
#include nagmk26.h
 Integer x06xaf_ ()

## 3Description

x06xaf can be used to determine whether you are using a serial or multi-threaded implementation of the NAG Library. In particular, with this information the behaviour of the other routines in this chapter can be predicted, as described in the X06 Chapter Introduction.
The routine returns $1$ when a multi-threaded implementation of the Library is being used and $0$ if a serial implementation is being used.

None.

None.

None.

Not applicable.

## 8Parallelism and Performance

x06xaf is not threaded in any implementation.