inq_ele_ptr(3G)

NAME

inq_ele_ptr, inq_ele_ptr_at_bound − return information about element pointer position within the currently open segment

SYNOPSIS

C Syntax:

void inq_ele_ptr(fildes, offset)
int fildes, *offset;

void inq_ele_ptr_at_bound(fildes, at_top, at_bot)
int fildes, *at_top, *at_bot;

FORTRAN77 Syntax:

subroutine inq_ele_ptr(fildes, offset)
integer*4 fildes, offset

subroutine inq_ele_ptr_at_bound(fildes, at_top, at_bot)
integer*4 fildes, at_top, at_bot

Pascal Syntax:

procedure inq_ele_ptr(fildes:integer;var offset:integer);

procedure inq_ele_ptr_at_bound(fildes:integer;
var at_top, at_bot:integer);

DESCRIPTION

Input Parameters

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

Output Parameters

offset Offset of the element pointer from the beginning of the currently open segment.

at_top Flag returning TRUE (1) if the element pointer is positioned at element 0 of the currently open segment; otherwise, FALSE (0).

at_bot Flag returning TRUE (1) if the element pointer is positioned at the last element of the currently open segment; otherwise, FALSE (0).

Discussion

Inq_ele_ptr returns the location of the element pointer within the currently open segment of the specified graphics device. Inq_ele_ptr returns the offset, in number of elements, from the beginning of the segment to the current element.

Inq_ele_ptr_at_bound returns an indication of where the element pointer is relative to the beginning and end of the segment. At_top will only be TRUE (1) if the element pointer is positioned at element 0 of the currently open segment. At_bot will only be TRUE (1) if the element pointer is positioned at the last element of the currently open segment. When the currently open segment is empty, both at_top and at_bot will be TRUE (1).

ERRORS

1 Graphics device not initialized for this operation.

24 Segment not open.

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