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XAllocClassHint(3X11)    XLIB FUNCTIONS     XAllocClassHint(3X11)



NAME
     XAllocClassHint, XSetClassHint, XGetClassHint, XClassHint -
     allocate class hints structure and set or read a window's
     WM_CLASS property

SYNTAX
     XClassHint *XAllocClassHint()

     XSetClassHint(display, w, class_hints)
           Display *display;
           Window w;
           XClassHint *class_hints;

     Status XGetClassHint(display, w, class_hints_return)
           Display *display;
           Window w;
           XClassHint *class_hints_return;

ARGUMENTS
     display   Specifies the connection to the X server.

     class_hints
               Specifies the XClassHint structure that is to be
               used.

     class_hints_return
               Returns the XClassHint structure.

     w         Specifies the window.

DESCRIPTION
     The XAllocClassHint function allocates and returns a pointer
     to a XClassHint structure.  Note that the pointer fields in
     the XClassHint structure are initially set to NULL.  If
     insufficient memory is available, XAllocClassHint returns
     NULL.  To free the memory allocated to this structure, use
     XFree.

     The XSetClassHint function sets the class hint for the
     specified window.  If the strings are not in the Host Port-
     able Character Encoding, the result is implementation depen-
     dent.

     XSetClassHint can generate BadAlloc and BadWindow errors.

     The XGetClassHint function returns the class hint of the
     specified window to the members of the supplied structure.
     If the data returned by the server is in the Latin Portable
     Character Encoding, then the returned strings are in the
     Host Portable Character Encoding.  Otherwise, the result is
     implementation dependent.  It returns a nonzero status on
     success; otherwise, it returns a zero status.  To free



X Version 11         Last change: Release 6                     1






XAllocClassHint(3X11)    XLIB FUNCTIONS     XAllocClassHint(3X11)



     res_name and res_class when finished with the strings, use
     XFree on each individually.

     XGetClassHint can generate a BadWindow error.

PROPERTIES
     WM_CLASS  Set by application programs to allow window and
               session managers to obtain the application's
               resources from the resource database.

STRUCTURES
     The XClassHint structure contains:

     typedef struct {
          char *res_name;
          char *res_class;
     } XClassHint;

     The res_name member contains the application name, and the
     res_class member contains the application class. Note that
     the name set in this property may differ from the name set
     as WM_NAME.  That is, WM_NAME specifies what should be
     displayed in the title bar and, therefore, can contain tem-
     poral information (for example, the name of a file currently
     in an editor's buffer).  On the other hand, the name speci-
     fied as part of WM_CLASS is the formal name of the applica-
     tion that should be used when retrieving the application's
     resources from the resource database.

DIAGNOSTICS
     BadAlloc  The server failed to allocate the requested
               resource or server memory.

     BadWindow A value for a Window argument does not name a
               defined Window.

SEE ALSO
     XAllocIconSize(3X11), XAllocSizeHints(3X11),
     XAllocWMHints(3X11), XFree(3X11), XSetCommand(3X11),
     XSetTransientForHint(3X11), XSetTextProperty(3X11),
     XSetWMClientMachine(3X11), XSetWMColormapWindows(3X11),
     XSetWMIconName(3X11), XSetWMName(3X11),
     XSetWMProperties(3X11), XSetWMProtocols(3X11),
     XStringListToTextProperty(3X11)
     Xlib - C Language X Interface










X Version 11         Last change: Release 6                     2



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