GPQIQO - Inquire Input Queue Overflow

Note:

This subroutine is a graPHIGS API State List (PSL) inquiry. For an overview, see "PSL Inquiries"

Purpose

Use GPQIQO to inquire identification of the event report causing the event queue overflow.

Once the event queue overflow occurs, no more events are added to the event queue until the overflow situation is cleared. The overflow situation is cleared when the event queue becomes empty. The application can make the event queue empty by using the Await Event (GPAWEV) subroutine, Flush Device Events (GPFLEV) subroutine, or the Flush Workstation Event (GPFWEV) subroutine.

If the event queue has overflowed since you last called the Open graPHIGS (GPOPPH) subroutine, the event class, major and minor codes of the event causing the overflow are returned (if the event class has corresponding major and minor codes)

The details of the possible event classes and meanings of their major and minor codes are shown in The graPHIGS Programming Interface: Technical Reference

The event queue overflow is not reported to the application when the overflow occurs. It is reported on the next invocation of the following subroutines which may change the contents of the event queue.

If the inquired information is available, then the graPHIGS API sets the error indicator to zero and returns the values in the output parameters. If the inquired information is unavailable, then the error indicator (errind) contains an error number indicating the reason, and the values returned in the output parameters are unpredictable.

Parameters