mojave man page for tk_getcolormap

Tk_GetColormap(3)					       Tk Library Procedures						 Tk_GetColormap(3)

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NAME
       Tk_GetColormap, Tk_PreserveColormap, Tk_FreeColormap - allocate and free colormaps

SYNOPSIS
       #include <tk.h>

       Colormap
       Tk_GetColormap(interp, tkwin, string)

       Tk_PreserveColormap(display, colormap)

       Tk_FreeColormap(display, colormap)

ARGUMENTS
       Tcl_Interp *interp (in)	       Interpreter to use for error reporting.

       Tk_Window tkwin (in)	       Token for window in which colormap will be used.

       const char *string (in)	       Selects a colormap:  either new or the name of a window with the same screen and visual as tkwin.

       Display *display (in)	       Display for which colormap was allocated.

       Colormap colormap (in)	       Colormap  to  free  or preserve;  must have been returned by a previous call to Tk_GetColormap or Tk_GetVi-
				       sual.
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DESCRIPTION
       These procedures are used to manage colormaps.  Tk_GetColormap returns a colormap suitable for use in tkwin.  If its string argument is new
       then a new colormap is created;	otherwise string must be the name of another window with the same screen and visual as tkwin, and the col-
       ormap from that window is returned.  If string does not make sense, or if it refers to a window on a different screen from tkwin or with  a
       different visual than tkwin, then Tk_GetColormap returns None and leaves an error message in interp's result.

       Tk_PreserveColormap  increases the internal reference count for a colormap previously returned by Tk_GetColormap, which allows the colormap
       to be stored in several locations without knowing which order they will be released.

       Tk_FreeColormap should be called when a colormap returned by Tk_GetColormap is no longer needed.  Tk maintains a reference count  for  each
       colormap  returned  by  Tk_GetColormap,	so there should eventually be one call to Tk_FreeColormap for each call to Tk_GetColormap and each
       call to Tk_PreserveColormap.  When a colormap's reference count becomes zero, Tk releases the X colormap.

       Tk_GetVisual and Tk_GetColormap work together, in that a new colormap created by Tk_GetVisual may later be returned by Tk_GetColormap.  The
       reference  counting  mechanism for colormaps includes both procedures, so callers of Tk_GetVisual must also call Tk_FreeColormap to release
       the colormap.  If Tk_GetColormap is called with a string value of new then the resulting colormap will never be returned  by  Tk_GetVisual;
       however, it can be used in other windows by calling Tk_GetColormap with the original window's name as string.

KEYWORDS
       colormap, visual

Tk									4.0							 Tk_GetColormap(3)