Tk_GetAnchorFromObj(3) Tk Library Procedures Tk_GetAnchorFromObj(3)______________________________________________________________________________NAME
Tk_GetAnchorFromObj, Tk_GetAnchor, Tk_NameOfAnchor - translate between
strings and anchor positions
SYNOPSIS
#include <tk.h>
int |
Tk_GetAnchorFromObj(interp, objPtr, anchorPtr) |
int
Tk_GetAnchor(interp, string, anchorPtr)
CONST char *
Tk_NameOfAnchor(anchor)ARGUMENTS
Tcl_Interp *interp (in) Interpreter to use for error report-
ing, or NULL.
Tcl_Obj *objPtr (in/out) ||
String value contains name of anchor |
point: n, ne, e, se, s, sw, w, nw, |
or center; internal rep will be mod- |
ified to cache corresponding |
Tk_Anchor. |
CONST |
char *string (in) | |
Same as objPtr except description of |
anchor point is passed as a string.
int *anchorPtr (out) Pointer to location in which to
store anchor position corresponding
to objPtr or string.
Tk_Anchor anchor (in) Anchor position, e.g.
TCL_ANCHOR_CENTER.
_________________________________________________________________DESCRIPTION
Tk_GetAnchorFromObj places in *anchorPtr an anchor position (enumerated |
type Tk_Anchor) corresponding to objPtr's value. The result will be |
one of TK_ANCHOR_N, TK_ANCHOR_NE, TK_ANCHOR_E, TK_ANCHOR_SE, |
TK_ANCHOR_S, TK_ANCHOR_SW, TK_ANCHOR_W, TK_ANCHOR_NW, or TK_ANCHOR_CEN- |
TER. Anchor positions are typically used for indicating a point on an |
object that will be used to position the object, e.g. TK_ANCHOR_N means |
position the top center point of the object at a particular place. |
Under normal circumstances the return value is TCL_OK and interp is |
unused. If string doesn't contain a valid anchor position or an abbre- |
viation of one of these names, TCL_ERROR is returned, *anchorPtr is |
unmodified, and an error message is stored in interp's result if interp |
isn't NULL. Tk_GetAnchorFromObj caches information about the return |
value in objPtr, which speeds up future calls to Tk_GetAnchorFromObj |
with the same objPtr. |
Tk_GetAnchor is identical to Tk_GetAnchorFromObj except that the |
description of the anchor is specified with a string instead of an |
object. This prevents Tk_GetAnchor from caching the return value, so |
Tk_GetAnchor is less efficient than Tk_GetAnchorFromObj.
Tk_NameOfAnchor is the logical inverse of Tk_GetAnchor. Given an
anchor position such as TK_ANCHOR_N it returns a statically-allocated
string corresponding to anchor. If anchor isn't a legal anchor value,
then ``unknown anchor position'' is returned.
KEYWORDS
anchor position
Tk 8.1 Tk_GetAnchorFromObj(3)
