NAME

sample_choice − return current choice value

SYNOPSIS

C Syntax:

void sample_choice ( fildes, ordinal, valid, value );
int fildes, ordinal, *valid, *value;

FORTRAN77 Syntax:

subroutine sample_choice ( fildes, ordinal, valid, value )
integer*4 fildes, ordinal, valid, value

Pascal Syntax:

procedure sample_choice ( fildes, ordinal:integer;
var valid, value:integer );

DESCRIPTION

Input Parameters

fildes Integer file descriptor returned by gopen when an I/O path to a graphics device is opened. 

ordinal Logical device number ranging from 1 to number of devices in this class. 

Output Parameters

valid TRUE (1) if a valid choice was returned,
FALSE (0) otherwise. 

value Current choice value. 

Discussion

Sample_choice returns the current value of the choice device specified by fildes and ordinal. This is the equivalent of a non-blocking read. 

SEE ALSO

Starbase Reference: request_choice(3G).  Starbase Graphics Techniques: "Starbase Input". 

Hewlett-Packard Company  —  November 03, 1994