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NAME

       wm - Communicate with window manager

SYNOPSIS

       wm option window ?args?
_________________________________________________________________________________________________

DESCRIPTION

       The wm command is used to interact with window managers in order to control such things as
       the title for a window, its geometry, or the increments  in  terms  of  which  it  may  be
       resized.   The  wm  command  can take any of a number of different forms, depending on the
       option argument.  All of the forms expect at least one additional argument, window,  which
       must be the path name of a top-level window.

       The legal forms for the wm command are:

       wm aspect window ?minNumer minDenom maxNumer maxDenom?
              If  minNumer, minDenom, maxNumer, and maxDenom are all specified, then they will be
              passed to the window manager and the window manager should use them  to  enforce  a
              range  of  acceptable  aspect  ratios  for  window.   The  aspect  ratio  of window
              (width/length)  will  be  constrained  to   lie   between   minNumer/minDenom   and
              maxNumer/maxDenom.   If  minNumer etc. are all specified as empty strings, then any
              existing aspect ratio restrictions are removed.  If minNumer  etc.  are  specified,
              then  the  command  returns  an  empty  string.   Otherwise,  it returns a Tcl list
              containing four elements, which are  the  current  values  of  minNumer,  minDenom,
              maxNumer,  and  maxDenom  (if  no  aspect restrictions are in effect, then an empty
              string is returned).

       wm attributes window

       wm attributes window ?option?

       wm attributes window ?option value option value...?
              This subcommand returns or sets platform  specific  attributes  associated  with  a
              window.  The  first  form  returns  a list of the platform specific flags and their
              values. The second form returns the value for the specific option. The  third  form
              sets one or more of the values. The values are as follows:

              All  platforms  support  the  following attributes (though X11 users should see the
              notes below):

              -alpha Specifies the alpha transparency level of the toplevel. It accepts  a  value
                     from  0.0  (fully  transparent)  to 1.0 (opaque).  Values outside that range
                     will be constrained.  Where not supported, the -alpha value remains at 1.0.

              -fullscreen
                     Places the window in a mode that takes up the entire screen, has no borders,
                     and  covers  the  general  use area (i.e. Start menu and taskbar on Windows,
                     dock and menubar on OSX, general window decorations on X11).

              -topmost
                     Specifies whether this  is  a  topmost  window  (displays  above  all  other
                     windows).

              On Windows, the following attributes may be set.

              -disabled
                     Specifies whether the window is in a disabled state.

              -toolwindow
                     Specifies a toolwindow style window (as defined in the MSDN).

              -transparentcolor
                     Specifies  the  transparent color index of the toplevel.  It takes any color
                     value accepted by Tk_GetColor.  If the empty string is specified  (default),
                     no transparent color is used.  This is supported on Windows 2000/XP+.  Where
                     not supported, the -transparentcolor value remains at {}.

              On Mac OS X, the following attributes may be set.

              -modified
                     Specifies the modification state  of  the  window  (determines  whether  the
                     window  close  widget  contains  the  modification indicator and whether the
                     proxy icon is draggable).

              -notify
                     Specifies process notification  state  (bouncing  of  the  application  dock
                     icon).

              -titlepath
                     Specifies  the  path  of the file referenced as the window proxy icon (which
                     can be dragged and dropped in lieu of the file's finder icon).

              -transparent
                     Makes the window content area transparent and turns off the  window  shadow.
                     For  the  transparency  to be effective, the toplevel background needs to be
                     set to a color with some alpha, e.g.  “systemTransparent”.

              On X11, the following attributes may be set. These are not supported by all  window
              managers, and will have no effect under older WMs.

              -type  Requests  that  the  window  should  be interpreted by the window manager as │
                     being of the specified type(s). This may cause the window to be decorated in │
                     a  different  way  or  otherwise  managed  differently,  though exactly what │
                     happens is entirely up to the window manager. A list of types may  be  used, │
                     in order of preference. The following values are mapped to constants defined │
                     in the EWMH specification (using others is possible, but not advised):       │

                     desktop                                                                      │
                            indicates a desktop feature,                                          │

                     dock                                                                         │
                            indicates a dock/panel feature,                                       │

                     toolbar                                                                      │
                            indicates a toolbar window that should be acting on behalf of another │
                            window, as indicated with wm transient,                               │

                     menu                                                                         │
                            indicates  a torn-off menu that should be acting on behalf of another │
                            window, as indicated with wm transient,                               │

                     utility                                                                      │
                            indicates a utility window (e.g., palette or toolbox) that should  be │
                            acting on behalf of another window, as indicated with wm transient,   │

                     splash                                                                       │
                            indicates a splash screen, displayed during application start up,     │

                     dialog                                                                       │
                            indicates a general dialog window, that should be acting on behalf of │
                            another window, as indicated with wm transient,                       │

                     dropdown_menu                                                                │
                            indicates a menu summoned from a menu bar, which should usually  also │
                            be set to be override-redirected (with wm overrideredirect),          │

                     popup_menu                                                                   │
                            indicates  a  popup  menu,  which  should  usually  also be set to be │
                            override-redirected (with wm overrideredirect),                       │

                     tooltip                                                                      │
                            indicates a tooltip window, which should usually also be  set  to  be │
                            override-redirected (with wm overrideredirect),                       │

                     notification                                                                 │
                            indicates  a  window  that provides a background notification of some │
                            event, which should usually also be  set  to  be  override-redirected │
                            (with wm overrideredirect),                                           │

                     combo                                                                        │
                            indicates  the  drop-down  list  of  a  combobox widget, which should │
                            usually  also   be   set   to   be   override-redirected   (with   wmoverrideredirect),                                                    │

                     dnd                                                                          │
                            indicates  a  window  that  represents something being dragged, which │
                            should usually  also  be  set  to  be  override-redirected  (with  wmoverrideredirect),                                                    │

                     normal                                                                       │
                            indicates a window that has no special interpretation.                │

              -zoomed
                     Requests  that  the window should be maximized. This is the same as wm state
                     zoomed on Windows and Mac OS X.

              On X11, changes to window attributes are  performed  asynchronously.  Querying  the
              value  of an attribute returns the current state, which will not be the same as the
              value most recently set if the window manager has not yet processed the request  or
              if it does not support the attribute.

       wm client window ?name?
              If  name  is  specified,  this command stores name (which should be the name of the
              host on which the application is executing) in window's WM_CLIENT_MACHINE  property
              for  use  by  the  window manager or session manager.  The command returns an empty
              string in this case.  If name is not specified, the command returns the  last  name
              set  in  a  wm client command for window.  If name is specified as an empty string,
              the command deletes the WM_CLIENT_MACHINE property from window.

       wm colormapwindows window ?windowList?
              This command is used to manipulate the WM_COLORMAP_WINDOWS property, which provides
              information to the window managers about windows that have private colormaps.

              If  windowList  is not specified, the command returns a list whose elements are the
              names of the  windows  in  the  WM_COLORMAP_WINDOWS  property.   If  windowList  is
              specified,  it consists of a list of window path names;  the command overwrites the
              WM_COLORMAP_WINDOWS property with the given windows and returns  an  empty  string.
              The  WM_COLORMAP_WINDOWS  property  should  normally contain a list of the internal
              windows within window whose colormaps differ from their parents.

              The order of the windows in the property indicates a  priority  order:  the  window
              manager will attempt to install as many colormaps as possible from the head of this
              list when window gets the colormap focus.  If window  is  not  included  among  the
              windows  in windowList, Tk implicitly adds it at the end of the WM_COLORMAP_WINDOWS
              property, so that its colormap is lowest in priority.  If wm colormapwindows is not
              invoked,  Tk  will  automatically set the property for each top-level window to all
              the internal windows whose colormaps differ from their  parents,  followed  by  the
              top-level  itself;   the order of the internal windows is undefined.  See the ICCCM
              documentation for more information on the WM_COLORMAP_WINDOWS property.

       wm command window ?value?
              If value is specified, this command stores value in  window's  WM_COMMAND  property
              for  use  by  the  window  manager  or session manager and returns an empty string.
              Value must have proper list structure;  the elements should contain  the  words  of
              the  command  used  to  invoke the application.  If value is not specified then the
              command returns the last value set in a wm command command for window.  If value is
              specified  as  an  empty  string,  the command deletes the WM_COMMAND property from
              window.

       wm deiconify window
              Arrange for window to be displayed in normal (non-iconified) form.  This is done by
              mapping the window.  If the window has never been mapped then this command will not
              map the window, but it will ensure that when the window is first mapped it will  be
              displayed  in  de-iconified  form.   On  Windows, a deiconified window will also be
              raised and be given the focus (made the active window).  Returns an empty string.

       wm focusmodel window ?active|passive?
              If active or passive is supplied as an optional argument to the  command,  then  it
              specifies  the  focus  model for window.  In this case the command returns an empty
              string.  If no additional argument  is  supplied,  then  the  command  returns  the
              current focus model for window.

              An  active  focus  model means that window will claim the input focus for itself or
              its descendants,  even  at  times  when  the  focus  is  currently  in  some  other
              application.  Passive means that window will never claim the focus for itself:  the
              window manager should give the focus to window at appropriate times.  However, once
              the  focus  has been given to window or one of its descendants, the application may
              re-assign the focus among  window's  descendants.   The  focus  model  defaults  to
              passive, and Tk's focus command assumes a passive model of focusing.

       wm forget window
              The  window  will  be unmapped from the screen and will no longer be managed by wm.
              Windows created with the toplevel command will be treated like frame  windows  once
              they  are  no  longer  managed  by  wm,  however,  the  -menu configuration will be
              remembered and the menus will return once the widget is managed again.

       wm frame window
              If window has been reparented by the window manager into a  decorative  frame,  the
              command  returns  the  platform  specific window identifier for the outermost frame
              that contains window (the window whose parent is the root  or  virtual  root).   If
              window  has  not been reparented by the window manager then the command returns the
              platform specific window identifier for window.

       wm geometry window ?newGeometry?
              If newGeometry is specified, then the geometry of window is changed  and  an  empty
              string is returned.  Otherwise the current geometry for window is returned (this is
              the most recent geometry specified either by manual resizing or in  a  wm  geometry
              command).    NewGeometry   has   the   form  =widthxheight±x±y,  where  any  of  =,
              widthxheight, or ±x±y may be omitted.   Width  and  height  are  positive  integers
              specifying  the  desired  dimensions  of window.  If window is gridded (see GRIDDED
              GEOMETRY MANAGEMENT below)  then  the  dimensions  are  specified  in  grid  units;
              otherwise they are specified in pixel units.

              X  and  y specify the desired location of window on the screen, in pixels.  If x is
              preceded by +, it specifies the number of pixels  between  the  left  edge  of  the
              screen and the left edge of window's border;  if preceded by - then x specifies the
              number of pixels between the right edge  of  the  screen  and  the  right  edge  of
              window's  border.   If  y  is  preceded by + then it specifies the number of pixels
              between the top of the screen and the top of window's border;  if y is preceded  by
              -  then it specifies the number of pixels between the bottom of window's border and
              the bottom of the screen.

              If newGeometry is specified as an empty string  then  any  existing  user-specified
              geometry  for window is cancelled, and the window will revert to the size requested
              internally by its widgets.

              Note that this is related to winfo geometry, but not the same. That can only  query
              the geometry, and always reflects Tk's current understanding of the actual size and
              location of window, whereas wm geometry allows both setting  and  querying  of  the
              window  manager's  understanding  of  the size and location of the window. This can
              vary significantly, for example to reflect the addition of decorative  elements  to
              window such as title bars, and window managers are not required to precisely follow
              the requests made through this command.

       wm grid window ?baseWidth baseHeight widthInc heightInc?
              This command indicates that window is to be managed as a gridded window.   It  also
              specifies  the  relationship  between  grid  units  and pixel units.  BaseWidth and
              baseHeight specify the number of grid units corresponding to the  pixel  dimensions
              requested  internally  by  window using Tk_GeometryRequest.  WidthInc and heightInc
              specify the number of pixels in each horizontal and vertical grid unit.  These four
              values  determine  a  range  of acceptable sizes for window, corresponding to grid-
              based widths and heights  that  are  non-negative  integers.   Tk  will  pass  this
              information to the window manager;  during manual resizing, the window manager will
              restrict the window's size to one of these acceptable sizes.

              Furthermore, during manual resizing the window manager will  display  the  window's
              current  size in terms of grid units rather than pixels.  If baseWidth etc. are all
              specified as empty strings, then window will no longer  be  managed  as  a  gridded
              window.  If baseWidth etc. are specified then the return value is an empty string.

              Otherwise  the return value is a Tcl list containing four elements corresponding to
              the current baseWidth, baseHeight, widthInc,  and  heightInc;   if  window  is  not
              currently gridded, then an empty string is returned.

              Note:  this  command  should not be needed very often, since the Tk_SetGrid library
              procedure and the setGrid option provide easier access to the same functionality.

       wm group window ?pathName?
              If pathName is specified, it gives the path name for  the  leader  of  a  group  of
              related  windows.   The  window  manager  may use this information, for example, to
              unmap all of the windows in a group when the group's leader is iconified.  PathName
              may  be  specified  as an empty string to remove window from any group association.
              If pathName is specified then the command returns an empty  string;   otherwise  it
              returns  the  path  name  of  window's  current group leader, or an empty string if
              window is not part of any group.

       wm iconbitmap window ?bitmap?
              If bitmap is specified, then it names a bitmap in the standard forms accepted by Tk
              (see  the  Tk_GetBitmap  manual  entry  for details).  This bitmap is passed to the
              window manager to be displayed in window's icon, and the command returns  an  empty
              string.   If  an empty string is specified for bitmap, then any current icon bitmap
              is cancelled for window.  If bitmap is specified then the command returns an  empty
              string.   Otherwise  it returns the name of the current icon bitmap associated with
              window, or an empty string if window has no icon bitmap.  On the Windows  operating
              system, an additional flag is supported:

              wm iconbitmap window ?-default? ?image?
                     If  the  -default flag is given, the icon is applied to all toplevel windows
                     (existing and future) to which no other specific icon has yet been  applied.
                     In  addition  to  bitmap  image types, a full path specification to any file
                     which contains a valid Windows icon is also accepted (usually .ico  or  .icr
                     files),  or  any  file  for  which the shell has assigned an icon.  Tcl will
                     first test if the file contains an icon, then if it has  an  assigned  icon,
                     and finally, if that fails, test for a bitmap.

       wm iconify window
              Arrange  for  window  to  be  iconified.  It window has not yet been mapped for the
              first time, this command will arrange for it to appear in the iconified state  when
              it is eventually mapped.

       wm iconmask window ?bitmap?
              If bitmap is specified, then it names a bitmap in the standard forms accepted by Tk
              (see the Tk_GetBitmap manual entry for details).  This  bitmap  is  passed  to  the
              window  manager  to  be  used  as a mask in conjunction with the iconbitmap option:
              where the mask has zeroes no icon will be displayed;  where it has ones,  the  bits
              from the icon bitmap will be displayed.  If an empty string is specified for bitmap
              then any current  icon  mask  is  cancelled  for  window  (this  is  equivalent  to
              specifying  a bitmap of all ones).  If bitmap is specified then the command returns
              an empty string.  Otherwise it returns the name of the current icon mask associated
              with window, or an empty string if no mask is in effect.

       wm iconname window ?newName?
              If  newName  is  specified,  then  it  is passed to the window manager;  the window
              manager should display newName inside the icon associated  with  window.   In  this
              case  an  empty string is returned as result.  If newName is not specified then the
              command returns the current icon name for window, or an empty  string  if  no  icon
              name  has been specified (in this case the window manager will normally display the
              window's title, as specified with the wm title command).

       wm iconphoto window ?-default? image1 ?image2 ...?
              Sets the titlebar icon for window based on the named photo images.  If -default  is
              specified,  this  is  applied to all future created toplevels as well.  The data in
              the images is taken as a snapshot at the time of invocation.   If  the  images  are
              later  changed,  this  is not reflected to the titlebar icons.  Multiple images are
              accepted to allow different images sizes (e.g., 16x16 and 32x32)  to  be  provided.
              The window manager may scale provided icons to an appropriate size.

              On  Windows,  the  images  are  packed  into  a  Windows icon structure.  This will
              override an ico specified to wm iconbitmap, and vice versa.

              On X, the images are arranged into the _NET_WM_ICON X property, which  most  modern
              window  managers  support.   A  wm  iconbitmap  may  exist  simultaneously.   It is
              recommended to use not more than 2 icons, placing the larger icon first.

              On Macintosh, the first image called is loaded into an OSX-native icon format,  and
              becomes  the  application  icon  in  dialogs,  the Dock, and other contexts. At the
              script level the command will accept only the first image passed in the  parameters
              as  support  for  multiple  sizes/resolutions  on  macOS  is  outside  Tk's  scope.
              Developers should use the largest icon they can support (preferably 512 pixels)  to
              ensure smooth rendering on the Mac.

       wm iconposition window ?x y?
              If  x  and  y  are specified, they are passed to the window manager as a hint about
              where to position the icon for window.  In this case an empty string  is  returned.
              If  x  and y are specified as empty strings then any existing icon position hint is
              cancelled.  If neither x nor y is specified, then the command returns  a  Tcl  list
              containing  two  values, which are the current icon position hints (if no hints are
              in effect then an empty string is returned).

       wm iconwindow window ?pathName?
              If pathName is specified, it is the path name for a  window  to  use  as  icon  for
              window: when window is iconified then pathName will be mapped to serve as icon, and
              when window is de-iconified then pathName will be unmapped again.  If  pathName  is
              specified  as  an empty string then any existing icon window association for window
              will be cancelled.  If the pathName argument is specified then an empty  string  is
              returned.   Otherwise  the command returns the path name of the current icon window
              for window, or an empty string if there is no icon window currently  specified  for
              window.   Button  press  events  are  disabled  for window as long as it is an icon
              window;  this is needed in order to allow window managers to  “own”  those  events.
              Note: not all window managers support the notion of an icon window.

       wm manage widget
              The  widget  specified will become a stand alone top-level window.  The window will
              be decorated with the window managers title bar, etc. Only  frame,  labelframe  and
              toplevel widgets can be used with this command. Attempting to pass any other widget
              type will raise an error. Attempting to manage a  toplevel  widget  is  benign  and
              achieves nothing. See also GEOMETRY MANAGEMENT.

       wm maxsize window ?width height?
              If width and height are specified, they give the maximum permissible dimensions for
              window.  For gridded windows the dimensions are specified in grid units;  otherwise
              they  are  specified in pixel units.  The window manager will restrict the window's
              dimensions to be less than or equal to width and height.  If width and  height  are
              specified,  then  the  command returns an empty string.  Otherwise it returns a Tcl
              list with two elements, which are the maximum width and height currently in effect.
              The  maximum size defaults to the size of the screen.  See the sections on geometry
              management below for more information.

       wm minsize window ?width height?
              If width and height are specified, they give the minimum permissible dimensions for
              window.  For gridded windows the dimensions are specified in grid units;  otherwise
              they are specified in pixel units.  The window manager will restrict  the  window's
              dimensions  to  be  greater than or equal to width and height.  If width and height
              are specified, then the command returns an empty string.  Otherwise  it  returns  a
              Tcl  list  with  two  elements, which are the minimum width and height currently in
              effect.  The minimum size defaults  to  one  pixel  in  each  dimension.   See  the
              sections on geometry management below for more information.

       wm overrideredirect window ?boolean?
              If  boolean  is  specified,  it  must  have a proper boolean form and the override-
              redirect flag for window is set to that value.  If boolean is not specified then  1
              or 0 is returned to indicate whether or not the override-redirect flag is currently
              set for window.  Setting the override-redirect flag for a window causes  it  to  be
              ignored by the window manager;  among other things, this means that the window will
              not be reparented from the root window into a decorative frame and  the  user  will
              not be able to manipulate the window using the normal window manager mechanisms.

              Note  that the override-redirect flag is only guaranteed to be taken notice of when
              the window is first mapped or when mapped after the state is changed from withdrawn
              to normal. Some, but not all, platforms will take notice at additional times.

       wm positionfrom window ?who?
              If  who  is specified, it must be either program or user, or an abbreviation of one
              of these two.  It indicates whether window's current position was requested by  the
              program  or  by  the  user.   Many window managers ignore program-requested initial
              positions and ask the user to manually position the window;  if user  is  specified
              then  the  window  manager  should  position  the window at the given place without
              asking the user for assistance.  If who is specified as an empty string,  then  the
              current  position  source  is  cancelled.   If  who  is specified, then the command
              returns an empty string.  Otherwise it returns user  or  program  to  indicate  the
              source  of  the window's current position, or an empty string if no source has been
              specified yet.  Most  window  managers  interpret  “no  source”  as  equivalent  to
              program.   Tk will automatically set the position source to user when a wm geometry
              command is invoked, unless the source has been set explicitly to program.

       wm protocol window ?name? ?command?
              This command is used to manage window manager protocols such  as  WM_DELETE_WINDOW.
              Name  is  the  name  of an atom corresponding to a window manager protocol, such as
              WM_DELETE_WINDOW or WM_SAVE_YOURSELF or WM_TAKE_FOCUS.  If both  name  and  command
              are  specified,  then  command  is  associated with the protocol specified by name.
              Name will be added to window's WM_PROTOCOLS property to  tell  the  window  manager
              that  the  application has a protocol handler for name, and command will be invoked
              in the future whenever the window manager sends a message to the  client  for  that
              protocol.   In this case the command returns an empty string.  If name is specified
              but command is not, then the current command for name  is  returned,  or  an  empty
              string  if  there  is  no  handler defined for name.  If command is specified as an
              empty string then the current handler for name is deleted and it  is  removed  from
              the  WM_PROTOCOLS  property  on  window;   an empty string is returned.  Lastly, if
              neither name nor command is specified, the  command  returns  a  list  of  all  the
              protocols for which handlers are currently defined for window.

              Tk  always  defines  a  protocol handler for WM_DELETE_WINDOW, even if you have not
              asked for one with wm protocol.  If a WM_DELETE_WINDOW  message  arrives  when  you
              have  not  defined  a handler, then Tk handles the message by destroying the window
              for which it was received.

       wm resizable window ?width height?
              This command controls whether or not the user may interactively resize a  top-level
              window.   If width and height are specified, they are boolean values that determine
              whether the width and height of window may be modified by the user.  In  this  case
              the  command  returns  an  empty  string.  If width and height are omitted then the
              command returns a list with two 0/1 elements that indicate whether  the  width  and
              height  of  window  are  currently resizable.  By default, windows are resizable in
              both dimensions.  If resizing is disabled, then the window's size will be the  size
              from  the most recent interactive resize or wm geometry command.  If there has been
              no such operation then the window's natural size will be used.

       wm sizefrom window ?who?
              If who is specified, it must be either program or user, or an abbreviation  of  one
              of  these  two.   It  indicates  whether window's current size was requested by the
              program or by the user.  Some window managers ignore  program-requested  sizes  and
              ask  the  user  to  manually size the window;  if user is specified then the window
              manager should give the window its specified  size  without  asking  the  user  for
              assistance.   If  who is specified as an empty string, then the current size source
              is cancelled.  If who is specified, then  the  command  returns  an  empty  string.
              Otherwise  it returns user or window to indicate the source of the window's current
              size, or an empty string if no source has been specified yet.  Most window managers
              interpret “no source” as equivalent to program.

       wm stackorder window ?isabove|isbelow window?
              The  stackorder  command returns a list of toplevel windows in stacking order, from
              lowest to highest. When a single toplevel  window  is  passed,  the  returned  list
              recursively  includes  all  of the window's children that are toplevels. Only those
              toplevels that are currently mapped to the screen  are  returned.   The  stackorder
              command  can also be used to determine if one toplevel is positioned above or below
              a second toplevel.  When two  window  arguments  separated  by  either  isabove  or
              isbelow  are  passed, a boolean result indicates whether or not the first window is
              currently above or below the second window in the stacking order.

       wm state window ?newstate?
              If newstate is specified, the window will be set to the  new  state,  otherwise  it
              returns  the  current  state  of window: either normal, iconic, withdrawn, icon, or
              (Windows and Mac OS X only) zoomed.  The difference between iconic and icon is that
              iconic  refers  to  a  window  that  has  been iconified (e.g., with the wm iconify
              command) while icon refers to a window whose only purpose is to serve as  the  icon
              for  some  other  window (via the wm iconwindow command).  The icon state cannot be
              set.

       wm title window ?string?
              If string is specified, then it will be passed to the window manager for use as the
              title  for  window (the window manager should display this string in window's title
              bar).  In this case the  command  returns  an  empty  string.   If  string  is  not
              specified then the command returns the current title for the window.  The title for
              a window defaults to its name.

       wm transient window ?master?
              If master is specified, then the window  manager  is  informed  that  window  is  a
              transient window (e.g. pull-down menu) working on behalf of master (where master is
              the path name for a top-level window).  If master is specified as an  empty  string
              then  window  is  marked  as  not being a transient window any more.  Otherwise the
              command returns the path name of window's current master, or  an  empty  string  if
              window  is  not currently a transient window.  A transient window will mirror state
              changes in the master and inherit the state of the master when initially mapped. It
              is  an error to attempt to make a window a transient of itself.  The window manager
              may also decorate a transient window differently, removing some  features  normally
              present  (e.g.,  minimize  and  maximize  buttons)  though  this is entirely at the
              discretion of the window manager.

       wm withdraw window
              Arranges for window to be withdrawn from the screen.  This causes the window to  be
              unmapped  and  forgotten about by the window manager.  If the window has never been
              mapped, then this command causes the window to be mapped in  the  withdrawn  state.
              Not all window managers appear to know how to handle windows that are mapped in the
              withdrawn state.  Note: it sometimes seems to be necessary to withdraw a window and
              then  re-map  it  (e.g.  with  wm  deiconify)  to  get  some window managers to pay
              attention to changes in window attributes such as group.

GEOMETRY MANAGEMENT

       By default a top-level window appears on the screen in its natural size, which is the  one
       determined internally by its widgets and geometry managers.  If the natural size of a top-
       level window changes, then the window's size changes to match.  A top-level window can  be
       given  a  size  other  than  its natural size in two ways.  First, the user can resize the
       window manually using the facilities of  the  window  manager,  such  as  resize  handles.
       Second,  the application can request a particular size for a top-level window using the wm
       geometry command.  These two cases are handled identically by Tk;   in  either  case,  the
       requested  size  overrides  the natural size.  You can return the window to its natural by
       invoking wm geometry with an empty geometry string.

       Normally a top-level window can have any size from one pixel in each dimension up  to  the
       size  of its screen.  However, you can use the wm minsize and wm maxsize commands to limit
       the range of allowable sizes.  The range set by wm minsize and wm maxsize applies  to  all
       forms  of  resizing, including the window's natural size as well as manual resizes and the
       wm geometry command.  You can also use the command  wm  resizable  to  completely  disable
       interactive resizing in one or both dimensions.

       The  wm  manage  and  wm  forget  commands may be used to perform undocking and docking of
       windows.  After a widget is managed by wm manage command, all other wm subcommands may  be
       used  with  the  widget.   Only  widgets  created  using  the toplevel command may have an
       attached menu via the -menu configure option.  A toplevel widget may be used  as  a  frame
       and  managed  with  any  of the other geometry managers after using the wm forget command.
       Any menu associated with a toplevel widget will be hidden when managed by another geometry
       managers.   The menus will reappear once the window is managed by wm.  All custom bindtags
       for widgets in a subtree that have their top-level widget changed via a wm  manage  or  wm
       forget  command,  must  be  redone  to  adjust  any top-level widget path in the bindtags.
       Bindtags that have not been customized do not have to be redone.

GRIDDED GEOMETRY MANAGEMENT

       Gridded geometry management occurs when one of the widgets of an  application  supports  a
       range  of  useful sizes.  This occurs, for example, in a text editor where the scrollbars,
       menus, and other adornments are fixed in size but the edit widget can support  any  number
       of lines of text or characters per line.  In this case, it is usually desirable to let the
       user specify the number of lines or  characters-per-line,  either  with  the  wm  geometry
       command  or  by  interactively  resizing  the  window.   In the case of text, and in other
       interesting cases also, only discrete sizes of the window make  sense,  such  as  integral
       numbers of lines and characters-per-line;  arbitrary pixel sizes are not useful.

       Gridded  geometry  management  provides support for this kind of application.  Tk (and the
       window manager) assume that there is a grid of some sort within the application  and  that
       the  application  should  be  resized  in terms of grid units rather than pixels.  Gridded
       geometry management is typically invoked by turning on the setGrid option  for  a  widget;
       it  can  also  be  invoked  with the wm grid command or by calling Tk_SetGrid.  In each of
       these approaches the particular widget (or sometimes code in the application as  a  whole)
       specifies the relationship between integral grid sizes for the window and pixel sizes.  To
       return to non-gridded geometry management, invoke wm grid with empty argument strings.

       When gridded geometry management is enabled  then  all  the  dimensions  specified  in  wm
       minsize,  wm maxsize, and wm geometry commands are treated as grid units rather than pixel
       units.  Interactive resizing is also carried out in even numbers of grid units rather than
       pixels.

BUGS

       Most  existing  window  managers  appear  to have bugs that affect the operation of the wm
       command.  For example, some changes will not take effect if the window is already  active:
       the window will have to be withdrawn and de-iconified in order to make the change happen.

EXAMPLES

       A fixed-size window that says that it is fixed-size too:
              toplevel .fixed
              wm title     .fixed "Fixed-size Window"
              wm resizable .fixed 0 0

       A simple dialog-like window, centred on the screen:
              # Create and arrange the dialog contents.
              toplevel .msg
              label  .msg.l  -text "This is a very simple dialog demo."
              button .msg.ok -text OK -default active -command {destroy .msg}
              pack .msg.ok -side bottom -fill x
              pack .msg.l  -expand 1    -fill both

              # Now set the widget up as a centred dialog.

              # But first, we need the geometry managers to finish setting
              # up the interior of the dialog, for which we need to run the
              # event loop with the widget hidden completely...
              wm withdraw .msg
              update
              set x [expr {([winfo screenwidth .]-[winfo width .msg])/2}]
              set y [expr {([winfo screenheight .]-[winfo height .msg])/2}]
              wm geometry  .msg +$x+$y
              wm transient .msg .
              wm title     .msg "Dialog demo"
              wm deiconify .msg

SEE ALSO

       toplevel(3tk), winfo(3tk)

KEYWORDS

       aspect  ratio,  deiconify,  focus model, geometry, grid, group, icon, iconify, increments,
       position, size, title, top-level window, units, window manager