The Xmu Library is a collection of miscellaneous (some might say random) utility functions that have been useful in building various applications and widgets. This library is required by the Athena Widgets.

Starting in XFree86 4.1.0, and incorporated into X11R6.7 and later releases, a subset of the functions that do not rely on the Athena Widgets (libXaw) or X Toolkit Instrinsics (libXt) are provided in a second library, libXmuu.

Programs using either of these libraries are encouraged to determine the correct compiler and linker options via the xmu or xmuu module names for pkg-config, such as:

cc -c xapplication.c `pkg-config --cflags xmu`
cc -o xapplication xapplication.o `pkg-config --libs xmu`
      

To use the functions and macros defined in this section, you should include the header file <X11/Xmu/Atoms.h> and link against the libXmu library.

These macros take a display as argument and return an Atom. The name of the atom is obtained from the macro name by removing the leading characters “XA_”. The Atom value is cached, such that subsequent requests do not cause another round-trip to the server.

This function creates and initializes an opaque object, an AtomPtr, for an Atom with the given name. XmuInternAtom can be used to cache the Atom value for one or more displays.

The function returns the name of an AtomPtr.

This function returns the Atom for an AtomPtr. The Atom is cached, such that subsequent requests do not cause another round-trip to the server.

This function returns the name of an Atom. The result is cached, such that subsequent requests do not cause another round-trip to the server.

This function converts a list of atom names into Atom values. The results are cached, such that subsequent requests do not cause further round-trips to the server. The caller is responsible for preallocating the array pointed at by atoms.

To use the functions defined in this section, you should include the header file <X11/Xmu/Error.h> and link against the libXmu or libXmuu library.

This function prints an error message, equivalent to Xlib's default error message for protocol errors. It returns a non-zero value if the caller should consider exiting, otherwise it returns 0. This function can be used when you need to write your own error handler, but need to print out an error from within that handler.

This function ignores errors for BadWindow errors for XQueryTree and XGetWindowAttributes, and ignores BadDrawable errors for XGetGeometry; it returns 0 in those cases. Otherwise, it prints the default error message, and returns a non-zero value if the caller should consider exiting, and 0 if the caller should not exit.

To use the functions defined in this section, you should include the header file <X11/Xmu/SysUtil.h> and link against the libXmu or libXmuu library.

This function stores the null terminated name of the local host in buf, and returns length of the name. This function hides operating system differences, such as whether to call gethostname or uname.

This function was provided as a portable implementation of snprintf before all platforms could be relied on to provide their own. It is now deprecated in favor of calling snprintf directly and should only be used in software that needs to continue to support non-Unix98 compliant platforms.

To use the functions defined in this section, you should include the header file <X11/Xmu/WinUtil.h> . To use XmuClientWindow, you may link against either the libXmu or libXmuu libraries. The other functions in this section require linking against the libXmu library.

This function returns the Screen on which the specified window was created.

This function finds a window, at or below the specified window, which has a WM_STATE property. If such a window is found, it is returned, otherwise the argument window is returned.

This function clears the PPosition and PSize flags and sets the USPosition and USSize flags in the hints structure, and then stores the hints for the window using XSetWMNormalHints and returns True. If NULL is passed for the hints structure, then the current hints are read back from the window using XGetWMNormalHints and are used instead, and True is returned; otherwise False is returned.

To use the functions defined in this section, you should include the header file <X11/Xmu/CurUtil.h> and link against the libXmu or libXmuu library.

This function takes the name of a standard cursor and returns its index in the standard cursor font. The cursor names are formed by removing the “XC_” prefix from the cursor defines listed in Appendix B of the Xlib manual.

To use the functions defined in this section, you should include the header file <X11/Xmu/Drawing.h> and link against the libXmu library.

This function draws a rounded rectangle, where x, y, w, h are the dimensions of the overall rectangle, and ew and eh are the sizes of a bounding box that the corners are drawn inside of; ew should be no more than half of w, and eh should be no more than half of h. The current GC line attributes control all attributes of the line.

This function draws a filled rounded rectangle, where x, y, w, h are the dimensions of the overall rectangle, and ew and eh are the sizes of a bounding box that the corners are drawn inside of; ew should be no more than half of w, and eh should be no more than half of h. The current GC fill settings control all attributes of the fill contents.

This function draws the “official” X Window System logo (Figure 1, “The X Logo”). The bounding box of the logo in the drawable is given by x, y, width, and height. The logo itself is filled using gcFore, and the rest of the rectangle is filled using gcBack.

This function creates a two pixel by one pixel stippled pixmap of specified depth on the specified screen. The pixmap is cached so that multiple requests share the same pixmap. The pixmap should be freed with XmuReleaseStippledPixmap to maintain correct reference counts.

This function frees a pixmap created with XmuCreateStippledPixmap.

This function reads a standard bitmap file description from the specified stream, and returns the parsed data in a format suitable for passing to XCreateBitmapFromData. The return value of the function has the same interpretation as the return value for XReadBitmapFile.

This function reads a standard bitmap file description from the specified file, and returns the parsed data in a format suitable for passing to XCreateBitmapFromData. The return value of the function has the same interpretation as the return value for XReadBitmapFile.

This function reads a file in standard bitmap file format, using XReadBitmapFile, and returns the created bitmap. The filename may be absolute, or relative to the global resource named bitmapFilePath with class BitmapFilePath. If the resource is not defined, the default value is the build symbol BITMAPDIR, which is typically "/usr/include/X11/bitmaps". If srcnamelen is greater than zero and srcname is not NULL, the null terminated filename will be copied into srcname. The size and hotspot of the bitmap are also returned.

This function creates a pixmap of the specified width, height, and depth, on the same screen as the specified drawable, and then performs an XCopyPlane from the specified bitmap to the pixmap, using the specified foreground and background pixel values. The created pixmap is returned.

To use the functions defined in this section, you should include the header file <X11/Xmu/StdSel.h> and link against the libXmu library.

This function converts the following standard selections: CLASS, CLIENT_WINDOW, DECNET_ADDRESS, HOSTNAME, IP_ADDRESS, NAME, OWNER_OS, TARGETS, TIMESTAMP, and USER. It returns True if the conversion was successful, else it returns False.

To use the functions defined in this section, you should include the header file <X11/Xmu/Converters.h> and link against the libXmu library.

This function converts a callback procedure to a callback list containing that procedure, with NULL closure data. To use this converter, include the following in your widget's ClassInitialize procedure:

XtAddConverter(XtRCallProc, XtRCallback, XmuCvtFunctionToCallback, NULL, 0);
      

This function converts a string to a backing-store integer as defined in <X11/X.h>. The string "notUseful" converts to NotUseful, "whenMapped" converts to WhenMapped, and "always" converts to Always. The string "default" converts to the value Always + WhenMapped + NotUseful. The case of the string does not matter. To use this converter, include the following in your widget's ClassInitialize procedure:

XtAddConverter(XtRString, XtRBackingStore, XmuCvtStringToBackingStore, NULL, 0);
      

This function creates a bitmap (a Pixmap of depth one) suitable for window manager icons. The string argument is the name of a file in standard bitmap file format. For the possible filename specifications, see XmuLocateBitmapFile. To use this converter, include the following in your widget's ClassInitialize procedure:

static XtConvertArgRec screenConvertArg[] = {
  {XtBaseOffset, (XtPointer)XtOffset(Widget, core.screen), sizeof(Screen *)}
};

XtAddConverter(XtRString, XtRBitmap, XmuCvtStringToBitmap,
		 screenConvertArg, XtNumber(screenConvertArg));
      

This function converts a string to a Cursor with the foreground and background pixels specified by the conversion arguments. The string can either be a standard cursor name formed by removing the “XC_” prefix from any of the cursor defines listed in Appendix B of the Xlib Manual, a font name and glyph index in decimal of the form "FONT fontname index [[font] index]", or a bitmap filename acceptable to XmuLocateBitmapFile. To use this converter, include the following in the widget ClassInitialize procedure:

static XtConvertArgRec colorCursorConvertArgs[] = {
  {XtWidgetBaseOffset, (XtPointer) XtOffsetOf(WidgetRec, core.screen),
   sizeof(Screen *)},
  {XtResourceString, (XtPointer) XtNpointerColor, sizeof(Pixel)},
  {XtResourceString, (XtPointer) XtNpointerColorBackground, sizeof(Pixel)},
  {XtWidgetBaseOffset, (XtPointer) XtOffsetOf(WidgetRec, core.colormap),
   sizeof(Colormap)}
};


XtSetTypeConverter(XtRString, XtRColorCursor, XmuCvtStringToColorCursor,
		 colorCursorConvertArgs, XtNumber(colorCursorConvertArgs),
                 XtCacheByDisplay, NULL);
      

The widget must recognize XtNpointerColor and XtNpointerColorBackground as resources, or specify other appropriate foreground and background resources. The widget's Realize and SetValues methods must cause the converter to be invoked with the appropriate arguments when one of the foreground, background, or cursor resources has changed, or when the window is created, and must assign the cursor to the window of the widget.

This function converts a string to a Cursor. The string can either be a standard cursor name formed by removing the “XC_” prefix from any of the cursor defines listed in Appendix B of the Xlib Manual, a font name and glyph index in decimal of the form "FONT fontname index [[font] index]", or a bitmap filename acceptable to XmuLocateBitmapFile. To use this converter, include the following in your widget's ClassInitialize procedure:

static XtConvertArgRec screenConvertArg[] = {
  {XtBaseOffset, (XtPointer)XtOffsetOf(WidgetRec, core.screen), sizeof(Screen *)}
};

XtAddConverter(XtRString, XtRCursor, XmuCvtStringToCursor,
		 screenConvertArg, XtNumber(screenConvertArg));
      

This function converts a string to an XtGravity enumeration value. The string "forget" and a NULL value convert to ForgetGravity, "NorthWestGravity" converts to NorthWestGravity, the strings "NorthGravity" and "top" convert to NorthGravity, "NorthEastGravity" converts to NorthEastGravity, the strings "West" and "left" convert to WestGravity, "CenterGravity" converts to CenterGravity, "EastGravity" and "right" convert to EastGravity, "SouthWestGravity" converts to SouthWestGravity, "SouthGravity" and "bottom" convert to SouthGravity, "SouthEastGravity" converts to SouthEastGravity, "StaticGravity" converts to StaticGravity, and "UnmapGravity" converts to UnmapGravity. The case of the string does not matter. To use this converter, include the following in your widget's class initialize procedure:

XtAddConverter(XtRString, XtRGravity, XmuCvtStringToGravity, NULL, 0);
      

This function converts a string to an XtJustify enumeration value. The string "left" converts to XtJustifyLeft, "center" converts to XtJustifyCenter, and "right" converts to XtJustifyRight. The case of the string does not matter. To use this converter, include the following in your widget's ClassInitialize procedure:

XtAddConverter(XtRString, XtRJustify, XmuCvtStringToJustify, NULL, 0);
      

This function converts a string to an integer of type long. It parses the string using sscanf with a format of "%ld". To use this converter, include the following in your widget's ClassInitialize procedure:

XtAddConverter(XtRString, XtRLong, XmuCvtStringToLong, NULL, 0);
      

This function converts a string to an XtOrientation enumeration value. The string "horizontal" converts to XtorientHorizontal and "vertical" converts to XtorientVertical. The case of the string does not matter. To use this converter, include the following in your widget's ClassInitialize procedure:

XtAddConverter(XtRString, XtROrientation, XmuCvtStringToOrientation, NULL, 0);
      

This function converts a string to an integer shape style. The string "rectangle" converts to XmuShapeRectangle, "oval" converts to XmuShapeOval, "ellipse" converts to XmuShapeEllipse, and "roundedRectangle" converts to XmuShapeRoundedRectangle. The case of the string does not matter. To use this converter, include the following in your widget's ClassInitialize procedure:

XtSetTypeConverter(XtRString, XtRShapeStyle, XmuCvtStringToShapeStyle,
		     NULL, 0, XtCacheNone, NULL);
      

This function reshapes the specified widget, using the Shape extension, to a rectangle, oval, ellipse, or rounded rectangle, as specified by shape_style ( XmuShapeRectangle, XmuShapeOval, XmuShapeEllipse, and XmuShapeRoundedRectangle, respectively). The shape is bounded by the outside edges of the rectangular extents of the widget. If the shape is a rounded rectangle, corner_width and corner_height specify the size of the bounding box that the corners are drawn inside of (see XmuFillRoundedRectangle); otherwise, corner_width and corner_height are ignored. The origin of the widget within its parent remains unchanged.

This function converts a string to an immediate child widget of the parent widget passed as an argument. Note that this converter only works for child widgets that have already been created; there is no lazy evaluation. The string is first compared against the names of the normal and popup children, and if a match is found the corresponding child is returned. If no match is found, the string is compared against the classes of the normal and popup children, and if a match is found the corresponding child is returned. The case of the string is significant. To use this converter, include the following in your widget's ClassInitialize procedure:

static XtConvertArgRec parentCvtArg[] = {
  {XtBaseOffset, (XtPointer)XtOffset(Widget, core.parent), sizeof(Widget)},
};

XtAddConverter(XtRString, XtRWidget, XmuCvtStringToWidget,
		 parentCvtArg, XtNumber(parentCvtArg));
      

This converter is identical in functionality to XmuCvtStringToWidget, except that it is a new-style converter, allowing the specification of a cache type at the time of registration. Most widgets will not cache the conversion results, as the application may dynamically create and destroy widgets, which would cause cached values to become illegal. To use this converter, include the following in the widget's class initialize procedure:

static XtConvertArgRec parentCvtArg[] = {
  {XtWidgetBaseOffset, (XtPointer)XtOffsetOf(WidgetRec, core.parent),
   sizeof(Widget)}
};

XtSetTypeConverter(XtRString, XtRWidget, XmuNewCvtStringToWidget,
		   parentCvtArg, XtNumber(parentCvtArg), XtCacheNone, NULL);
      

To use the functions defined in this section, you should include the header file <X11/Xmu/CharSet.h> and link against the libXmu or libXmuu library.

This function copies a null terminated string from src to dst (including the null), changing all Latin-1 uppercase letters to lowercase. The string is assumed to be encoded using ISO 8859-1.

Note that like strcpy the caller is responsible for ensuring the size of dst is at least as large as the size of src.

This function copies up to size - 1 characters of a null terminated string from src to dst, and terminates it with a null, changing all Latin-1 uppercase letters to lowercase. The string is assumed to be encoded using ISO 8859-1.

This function copies a null terminated string from src to dst (including the null), changing all Latin-1 lowercase letters to uppercase. The string is assumed to be encoded using ISO 8859-1.

Note that like strcpy the caller is responsible for ensuring the size of dst is at least as large as the size of src.

This function copies up to size - 1 characters of a null terminated string from src to dst, and terminates it with a null, changing all Latin-1 lowercase letters to uppercase. The string is assumed to be encoded using ISO 8859-1.

This function compares two null terminated Latin-1 strings, ignoring case differences, and returns an integer greater than, equal to, or less than 0, according to whether first is lexicographically greater than, equal to, or less than second. The two strings are assumed to be encoded using ISO 8859-1.

To use the functions defined in this section, you should include the header file <X11/Xmu/Lookup.h> . and link against the libXmu library.

This function is identical to XLookupString, and exists only for naming symmetry with other functions.

This function is similar to XLookupString, except that it maps a key event to an Latin-2 (ISO 8859-2) string, or to an ASCII control string.

This function is similar to XLookupString, except that it maps a key event to an Latin-3 (ISO 8859-3) string, or to an ASCII control string.

This function is similar to XLookupString, except that it maps a key event to an Latin-4 (ISO 8859-4) string, or to an ASCII control string.

This function is similar to XLookupString, except that it maps a key event to a string in an encoding consisting of Latin-1 (ISO 8859-1) and ASCII control in the Graphics Left half (values 0 to 127), and Katakana in the Graphics Right half (values 128 to 255), using the values from JIS X201-1976.

This function is similar to XLookupString, except that it maps a key event to a string in the JIS X0201-1976 encoding, including ASCII control.

This function is similar to XLookupString, except that it maps a key event to a Latin/Arabic (ISO 8859-6) string, or to an ASCII control string.

This function is similar to XLookupString, except that it maps a key event to a Latin/Cyrillic (ISO 8859-5) string, or to an ASCII control string.

This function is similar to XLookupString, except that it maps a key event to a Latin/Greek (ISO 8859-7) string, or to an ASCII control string.

This function is similar to XLookupString, except that it maps a key event to a Latin/Hebrew (ISO 8859-8) string, or to an ASCII control string.

This function is similar to XLookupString, except that it maps a key event to an APL string.

The functions defined in this section are for parsing Compound Text strings, decomposing them into individual segments. Definitions needed to use these routines are in the include file <X11/Xmu/Xct.h> and link against the libXmu library.

A Compound Text string is represented as the following type:

	typedef unsigned char *XctString;
      

This function creates an XctData structure for parsing a Compound Text string. The string need not be null terminated. The following flags are defined to control parsing of the string:

This function resets the XctData structure to reparse the Compound Text string from the beginning.

This function parses the next “item” from the Compound Text string. The return value indicates what kind of item is returned. The item itself, its length, and the current contextual state, are reported as components of the XctData structure. XctResult is an enumeration, with the following values:

The following state values are stored in the XctData structure:

    XctString		item;		/* the action item */
    unsigned		item_length;	/* length of item in bytes */
    int			char_size;	/* the number of bytes per character in
					 * item, with zero meaning variable */
    char		*encoding;	/* the XLFD encoding name for item */
    XctHDirection	horizontal;	/* the direction of item */
    unsigned		horz_depth;	/* the current direction nesting depth */
    char		*GL;		/* the "{I} F" string for the current GL */
    char		*GL_encoding;	/* the XLFD encoding name for the current GL */
    int			GL_set_size;	/* 94 or 96 */
    int			GL_char_size;	/* the number of bytes per GL character */
    char		*GR;		/* the "{I} F" string for the current GR */
    char		*GR_encoding;	/* the XLFD encoding name for the current GR */
    int			GR_set_size;	/* 94 or 96 */
    int			GR_char_size;	/* number of bytes per GR character */
    char		*GLGR_encoding;	/* the XLFD encoding name for the current
					 *  GL+GR, if known */
	

This function frees all data associated with the XctData structure.

To use the functions defined in this section, you should include the header file <X11/Xmu/CloseHook.h> and link against the libXmu library.

This function adds a callback for the given display. When the display is closed, the given function will be called with the given display and argument as:

	(*func)(dpy, arg)
      

The function is declared to return an int even though the value is ignored, because some compilers used to have problems with functions returning void.

This routine returns NULL if it was unable to add the callback, otherwise it returns an opaque handle that can be used to remove or lookup the callback.

This function deletes a callback that has been added with XmuAddCloseDisplayHook. If handle is not NULL, it specifies the callback to remove, and the func and arg parameters are ignored. If handle is NULL, the first callback found to match the specified func and arg will be removed. Returns True if a callback was removed, else returns False.

This function determines if a callback is installed. If handle is not NULL, it specifies the callback to look for, and the func and arg parameters are ignored. If handle is NULL, the function will look for any callback for the specified func and arg. Returns True if a matching callback exists, else returns False.

To use the functions and types defined in this section, you should include the header file <X11/Xmu/DisplayQue.h> and link against the libXmu library. DisplayQue.h defines the following types:

typedef int (*XmuCloseDisplayQueueProc)(XmuDisplayQueue *queue,
                                        XmuDisplayQueueEntry *entry);

typedef int (*XmuFreeDisplayQueueProc)(XmuDisplayQueue *queue);

typedef struct _XmuDisplayQueueEntry {
	struct _XmuDisplayQueueEntry *prev, *next;
	Display *display;
	CloseHook closehook;
	XPointer data;
} XmuDisplayQueueEntry;

typedef struct _XmuDisplayQueue {
	int nentries;
	XmuDisplayQueueEntry *head, *tail;
	XmuCloseDisplayQueueProc closefunc;
	XmuFreeDisplayQueueProc freefunc;
	XPointer data;
} XmuDisplayQueue;
      

This function creates and returns an empty XmuDisplayQueue (which is really just a set of displays, but is called a queue for historical reasons). The queue is initially empty, but displays can be added using XmuAddDisplay. The data value is simply stored in the queue for use by the closefunc and freefunc callbacks. Whenever a display in the queue is closed using XCloseDisplay, the closefunc (if non-NULL) is called with the queue and the display's XmuDisplayQueueEntry as follows:

	(*closefunc)(queue, entry)
      

The freefunc (if non-NULL) is called whenever the last display in the queue is closed, as follows:

	(*freefunc)(queue)
      

The application is responsible for actually freeing the queue, by calling XmuDQDestroy.

This function adds the specified display to the queue. If successful, the queue entry is returned, otherwise NULL is returned. The data value is simply stored in the queue entry for use by the queue's freefunc callback. This function does not attempt to prevent duplicate entries in the queue; the caller should use XmuDQLookupDisplay to determine if a display has already been added to a queue.

This function returns the queue entry for the specified display, or NULL if the display is not in the queue.

This macro returns the number of displays in the specified queue.

This function removes the specified display from the specified queue. No callbacks are performed. If the display is not found in the queue, False is returned, otherwise True is returned.

This function releases all memory associated with the specified queue. If docallbacks is True, then the queue's closefunc callback (if non-NULL) is first called for each display in the queue, even though XCloseDisplay is not called on the display.

To use the functions defined in this section, you should include the header file <X11/Xmu/Initer.h> and link against the libXmu library.

This function registers a procedure, to be invoked the first time XmuCallInitializers is called on a given application context. The procedure is called with the application context and the specified data:

	(*func)(app_con, data)
      

This function calls each of the procedures that have been registered with XmuAddInitializer, if this is the first time the application context has been passed to XmuCallInitializers. Otherwise, this function does nothing.

To use the functions defined in this section, you should include the header file <X11/Xmu/StdCmap.h> and link against the libXmu library.

To create all of the appropriate standard colormaps for every visual of every screen on a given display, use XmuAllStandardColormaps.

This function defines and retains as permanent resources all standard colormaps which are meaningful for the visuals of each screen of the display. It returns 0 on failure, non-zero on success. If the property of any standard colormap is already defined, this function will redefine it.

This function is intended to be used by window managers or a special client at the start of a session.

The standard colormaps of a screen are defined by properties associated with the screen's root window. The property names of standard colormaps are predefined, and each property name except RGB_DEFAULT_MAP may describe at most one colormap.

The standard colormaps are: RGB_BEST_MAP, RGB_RED_MAP, RGB_GREEN_MAP, RGB_BLUE_MAP, RGB_DEFAULT_MAP, and RGB_GRAY_MAP. Therefore a screen may have at most 6 standard colormap properties defined.

A standard colormap is associated with a particular visual of the screen. A screen may have multiple visuals defined, including visuals of the same class at different depths. Note that a visual id might be repeated for more than one depth, so the visual id and the depth of a visual identify the visual. The characteristics of the visual will determine which standard colormaps are meaningful under that visual, and will determine how the standard colormap is defined. Because a standard colormap is associated with a specific visual, there must be a method of determining which visuals take precedence in defining standard colormaps.

The method used here is: for the visual of greatest depth, define all standard colormaps meaningful to that visual class, according to this order of (descending) precedence: DirectColor; PseudoColor; TrueColor and GrayScale; and finally StaticColor and StaticGray.

This function allows success, on a per screen basis. For example, if a map on screen 1 fails, the maps on screen 0, created earlier, will remain. However, none on screen 1 will remain. If a map on screen 0 fails, none will remain.

See XmuVisualStandardColormaps for which standard colormaps are meaningful under these classes of visuals.

To create all of the appropriate standard colormaps for a given visual on a given screen, use XmuVisualStandardColormaps.

This function defines all appropriate standard colormap properties for the given visual. If replace is True, any previous definition will be removed. If retain is True, new properties will be retained for the duration of the server session. This function returns 0 on failure, non-zero on success. On failure, no new properties will be defined, but old ones may have been removed if replace was True.

Not all standard colormaps are meaningful to all visual classes. This routine will check and define the following properties for the following classes, provided that the size of the colormap is not too small. For DirectColor and PseudoColor: RGB_DEFAULT_MAP, RGB_BEST_MAP, RGB_RED_MAP, RGB_GREEN_MAP, RGB_BLUE_MAP, and RGB_GRAY_MAP. For TrueColor and StaticColor: RGB_BEST_MAP. For GrayScale and StaticGray: RGB_GRAY_MAP.

To create a standard colormap if one does not currently exist, or replace the currently existing standard colormap, use XmuLookupStandardColormap.

Given a screen, a visual, and a property, this function will determine the best allocation for the property under the specified visual, and determine the whether to create a new colormap or to use the default colormap of the screen.

If replace is True, any previous definition of the property will be replaced. If retain is True, the property and the colormap will be made permanent for the duration of the server session. However, pre-existing property definitions which are not replaced cannot be made permanent by a call to this function; a request to retain resources pertains to newly created resources.

This function returns 0 on failure, non-zero on success. A request to create a standard colormap upon a visual which cannot support such a map is considered a failure. An example of this would be requesting any standard colormap property on a monochrome visual, or, requesting an RGB_BEST_MAP on a display whose colormap size is 16.

To determine the best allocation of reds, greens, and blues in a standard colormap, use XmuGetColormapAllocation.

XmuGetColormapAllocation returns 0 on failure, non-zero on success. It is assumed that the visual is appropriate for the colormap property.

To create any one standard colormap, use XmuStandardColormap.

This function creates a standard colormap for the given screen, visualid, and visual depth, with the given red, green, and blue maximum values, with the given standard property name. Upon success, it returns a pointer to an XStandardColormap structure which describes the newly created colormap. Upon failure, it returns NULL. If cmap is the default colormap of the screen, the standard colormap will be defined on the default colormap; otherwise a new colormap is created.

Resources created by this function are not made permanent; that is the caller's responsibility.

To create any one colormap which is described by an XStandardColormap structure, use XmuCreateColormap.

This function returns 0 on failure, and non-zero on success. The base_pixel of the colormap is set on success. Resources created by this function are not made permanent. No argument error checking is provided; use at your own risk.

All colormaps are created with read-only allocations, with the exception of read-only allocations of colors which fail to return the expected pixel value, and these are individually defined as read/write allocations. This is done so that all the cells defined in the colormap are contiguous, for use in image processing. This typically happens with White and Black in the default map.

Colormaps of static visuals are considered to be successfully created if the map of the static visual matches the definition given in the standard colormap structure.

To remove any standard colormap property, use XmuDeleteStandardColormap. This function will remove the specified property from the specified screen, releasing any resources used by the colormap(s) of the property, if possible.

The functions defined in this section are for building a description of the structure of and resources associated with a hierarchy of widget classes. This package is typically used by applications that wish to manipulate the widget set itself.

The definitions needed to use these interfaces are in the header file <X11/Xmu/WidgetNode.h> . To call these functions, you need to link against the libXmu library. The following function must be called before any of the others described below:

To determine the resources provided by a widget class or classes, use

Each widget class inherits the resources of its parent. To count the number of resources contributed by a particular widget class, use:

This routine returns the number of resources contributed (or “owned”) by the specified widget class.

This function returns the WidgetNode in the list that matches the given widget name or widget class name. If no match is found, it returns NULL.

To participate in the editres protocol, applications which are not based on the Athena widget set should include the header file <X11/Xmu/Editres.h> and link against the libXmu library.

To participate in the editres protocol, Xt applications which do not rely on the Athena widget set should register the editres protocol handler on each shell widget in the application, specifying an event mask of 0, nonmaskable events, and client data as NULL:

XtAddEventHandler(shell, (EventMask) 0, True, _XEditResCheckMessages, NULL);