qtest Subroutine

Purpose

Checks the contents of the event queue.

Libraries

Graphics Library

C (libgl.a)

FORTRAN (libfgl.a)

C Syntax

Int32 qtest( )

FORTRAN Syntax

INTEGER*4 FUNCTION QTEST

Description

The qtest subroutine returns zero if the event queue is empty. Otherwise, it returns the device number of the first entry. The queue remains unchanged.

Note: This subroutine cannot be used to add to a display list.

Return Value

The device number of the first entry (0 if the event queue is empty).

Example

The example C language program scrn_rotate.c uses the qtest subroutine to check if there is any input from the queued devices.

Implementation Specifics

This subroutine is part of GL in the AIXwindows Environment/6000 Version 1, Release 2 with AIXwindows/3D Feature.

Files

Related Information

Creating an event queue entry with the qenter subroutine.

Reading the first entry in the event queue with the qread subroutine.

Emptying the event queue with the qreset subroutine.

AIX Graphics Library Overview and Controlling Queues and Devices.