getanchor(3) - Linux man page

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 reporting, 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 modified 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_CENTER. 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 │ abbreviation 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