Tk_GetAnchorFromObj(3)Tk Library ProceduresTk_GetAnchorFromObj(3)



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NAME
       Tk_GetAnchorFromObj,   Tk_GetAnchor,   Tk_NameOfAnchor   -
       translate between strings and anchor positions

SYNOPSIS
       #include 

       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.
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DESCRIPTION
       Tk_GetAnchorFromObj  places  in *anchorPtr an anchor posi- |
       tion (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 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



Tk                             8.1         Tk_GetAnchorFromObj(3)