XAllocClassHint(3X11)       X Version 11(Release 5)       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 Portable Character Encoding the result
      is implementation dependent.

      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 nonzero status on
      success; otherwise it returns a zero status.  To free res_name and
      res_class when finished with the strings, use XFree on each individually.

      XGetClassHint can generate a BadWindow error.




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XAllocClassHint(3X11)       X Version 11(Release 5)       XAllocClassHint(3X11)


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 temporal information (for example, the name of a file currently
      in an editor's buffer).  On the other hand, the name specified as part of
      WM_CLASS is the formal name of the application 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


















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