XAllocWMHints(3X)                               XAllocWMHints(3X)



NAME
     XAllocWMHints, XSetWMHints, XGetWMHintsXWMHints  -  allocate
     an  XWMHints  structure and set and read a window's WM_HINTS
     property

SYNOPSIS
     XWMHints *XAllocWMHints()

     XSetWMHints(display, w, wmhints)
     Display *display;
     Window w;
     XWMHints *wmhints;

     XWMHints *XGetWMHints(display, w)
     Display *display;
     Window w;

DESCRIPTION
     The XAllocWMHints function allocates and returns a pointer
     to a XWMHints structure.  Note that all members of the
     XWMHints structure are initially set to 0.  If insufficient
     memory is available, XAllocWMHints returns NULL.  To free
     the memory allocated to this structure, use XFree.

     The XSetWMHints function sets the window manager hints that
     include icon information and location, the initial state of
     the window, and whether the application relies on the window
     manager to get keyboard input.

     The XGetWMHints function reads the window manager hints and
     returns NULL if no WM_HINTS property was set on the window
     or returns a pointer to a XWMHints structure if it succeeds.
     When finished with the data, free the space used for it by
     calling XFree.

   Arguments
     These functions accept the following arguments:

     display Specifies the connection to the X server.

     w       Specifies the window.

     wmhints Specifies the XWMHints structure to be used.

   Properties
     These functions use the following property:

     WM_HINTS
             Specifies additional hints set by client for use by
             the window manager.  The C type of this property is
             XWMHints.




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XAllocWMHints(3X)                               XAllocWMHints(3X)



   Structures
     The XWMHints structure is defined as follows.

     /* Window manager hints mask bits */
     #define InputHint   (1L << 0)
     #define StateHint   (1L << 1)
     #define IconPixmapHint   (1L << 2)
     #define IconWindowHint   (1L << 3)
     #define IconPositionHint (1L << 4)
     #define IconMaskHint     (1L << 5)
     #define WindowGroupHint  (1L << 6)
     #define AllHints         (InputHint|StateHint|
                  IconPixmapHint| IconWindowHint|
                  IconPositionHint|IconMaskHint|
                  WindowGroupHint)
     /* Values */
     typedef struct {
       long flags;       /* marks which members of */
                     /* this structure are defined */
       Bool input;       /* does this application */
                     /* rely on the window */
                     /* manager to get keyboard */
                     /* input? */
       int initial_state;     /* see below */
       Pixmap icon_pixmap;    /* pixmap to be used as icon */
       Window icon_window;    /* window to be used as icon */
       int icon_x, icon_y;    /* initial position of icon */
       Pixmap icon_mask; /* pixmap to be used as mask */
                     /* for icon_pixmap */
       XID window_group; /* id of related window group */
                     /* this structure may be */
                     /* extended in the future */
     } XWMHints;

     The input member is used to communicate to the window
     manager the input focus model used by the application.  Ap-
     plications that expect input but never explicitly set focus
     to any of their subwindows (that is, use the push model of
     focus management), such as X10-style applications that use
     real-estate driven focus, should set this member to TRUE.
     Similarly, applications that set input focus to their
     subwindows only when it is given to their top-level window
     by a window manager should also set this member to TRUE.
     Applications that manage their own input focus by explicitly
     setting focus to one of their subwindows whenever they want
     keyboard input (that is, use the pull model of focus manage-
     ment) should set this member to FALSE.  Applications that
     never expect any keyboard input also should set this member
     to FALSE.

     Pull model window managers should make it possible for push
     model applications to get input by setting input focus to



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XAllocWMHints(3X)                               XAllocWMHints(3X)



     the top-level windows of applications whose input member is
     TRUE.  Push model window managers should make sure that pull
     model applications do not break them by resetting input
     focus to
     PointerRoot when it is appropriate (for example, whenever an
     application whose input member is FALSE sets input focus to
     one of its subwindows).

     The definitions for initial_state flag are:

        #define WithdrawnState   0
        #define NormalState      1 /* most applications start */
                         /* this way */
        #define IconicState      3 /* application wants to */
                         /* start as an icon */

     The icon_mask specifies which pixels of the icon_pixmap
     should be used as the icon. This allows for nonrectangular
     icons.  Both icon_pixmap and icon_mask must be bitmaps.  The
     icon_window lets an application provide a window for use as
     an icon for window managers that support such use.  The
     window_group lets you specify that this window belongs to a
     group of other windows.  For example, if a single applica-
     tion manipulates multiple top-level windows, this allows you
     to provide enough information that a window manager can
     iconify all of the windows rather than just the one window.

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

     BadWindow
             A value for a Window argument does not name a de-
             fined Window.

     The XSetWMHints functions can generate BadAlloc and BadWin-
     dow errors.

     The XGetWMHints function can generate a BadWindow error.

SEE ALSO
     XAllocClassHint(3X), XAllocIconSize(3X),
     XAllocSizeHints(3X), XFree(3X), XSetCommand(3X),
     XSetTransientForHint(3X), XSetTextProperty(3X),
     XSetWMClientMachine(3X), XSetWMColormapWindows(3X),
     XSetWMIconName(3X), XSetWMName(3X), XSetWMProperties(3X),
     XSetWMProtocols(3X), XStringListToTextProperty(3X)

     Xlib - C Language Interface






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