inq_ele_control(3G)

NAME

inq_ele_control − return information about the element control flags of the current element of the currently open segment.

SYNOPSIS

C Syntax:

void inq_ele_control(fildes, control)
int fildes, *control;

FORTRAN77 Syntax:

subroutine inq_ele_control(fildes, control)
integer*4 fildes, control

Pascal Syntax:

procedure inq_ele_control(fildes: integer;
var control: integer);

DESCRIPTION

Input Parameters

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

Output Parameters

control the element control flags currently on for the current element.

Discussion

Inq_ele_control returns information about how the current element of the currently open segment is processed during display and pick traversals.

The return value control will be a bitwise combination of the following values:

DISP_IGNORE if the element is ignored during display traversals.

PICK_IGNORE if the element is ignored during pick traversals.

ERRORS

1 Graphics device is not initialized for this operation.

24 Segment not open.

36 Element pointer at element 0.

WARNING

Certain special elements (such as set_pick_traversal_control(3G) and application_data(3G)) are normally ignored during display and/or pick traversal. Such elements are always marked to be ignored during their respective traversals, and cannot be marked differently by the programmer. (See the sbdl(3G) manual page for those elements which are always marked to be ignored and on which traversals.) For example, set_pick_traversal_control elements are normally ignored during display processing. Thus, any call to inq_ele_control(3G) while the current element pointer is pointing at such an element will always indicate that the element is at least DISP_IGNORE. If the element has been marked by the programmer to be ignored during pick traversals as well, inq_ele_control will return (DISP_IGNORE + PICK_IGNORE).

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