FvwmBacker(1)                    Fvwm Modules                    FvwmBacker(1)

       FvwmBacker - the fvwm background changer module

       Module FvwmBacker

       FvwmBacker can only be invoked by fvwm.  Command line invocation of the
       FvwmBacker module will not work.

       The FvwmBacker module provides functionality to change the background
       when changing desktops.  Any command can be executed to change the
       backgrounds.  Actually, any arbitrary command can be sent to fvwm to
       execute, so you could also do things such as changing window border
       colors, etc.

       The FvwmBacker module is the original work of Mike Finger.

       Copyright 1994, Mike Finger. The author makes no guarantees or
       warranties of any kind about the use of this module.  Use this module
       at your own risk.  You may freely use this module or any portion of it
       for any purpose as long as the copyright is kept intact.

       During initialization, FvwmBacker gets config info from fvwm's module
       configuration database (see fvwm(1), section MODULE COMMANDS).
       Available options are discussed in a later section.

       FvwmBacker can be invoked by fvwm during initialization by inserting
       the line

       AddToFunc StartFunction I Module FvwmBacker

       in the .fvwm2rc file.

       FvwmBacker can be started using a 'Module FvwmBacker' command or
       stopped using a 'KillModule FvwmBacker' command at any time when fvwm
       is running.

       FvwmBacker must reside in a directory that is listed in the ModulePath
       option of fvwm for it to be executed by fvwm.

       The following options can be placed in the .fvwm2rc file

       *FvwmBacker: Command (Desk d, Page x y) command
              Specifies the command to execute when the viewport matches the
              arguments for the desk d, page x coordinate and y coordinate.
              Any or all of these three numeric arguments can be replaced with
              an asterisk (*) to indicate that any value matches, in this case
              Desk or Page parts can be skipped.

              If either the Desk or the Page parts are omitted, the command is
              not executed if only the desk or the page is switched.  If
              neither is given, the command is executed only once when the
              module is started.  This is not the same as using asterisks for
              the numeric arguments:  if asterisks are used, the command is
              always executed when only the desk or page changes, if the
              corresponding part is omitted, the command is never executed
              when only the desk or page changes.

              If the command is -solid FvwmBacker uses the next argument as a
              color in the X database and sets the background to that color
              without generating a system call to xsetroot (only single word
              color names may be used).

              If the command is colorset FvwmBacker uses the background
              specified in colorset n for the given desk.  Please refer to the
              fvwm man page for details about colorsets.

              Otherwise the command is sent to fvwm to execute.

       *FvwmBacker: RetainPixmap
              Causes FvwmBacker to retain and publish the Pixmap with which
              the background has been set. This works only for the -solid or
              colorset commands. This is useful for applications which want to
              use the root Pixmap on the background to simulate transparency
              (for example, Eterm and Aterm use this method). This option
              should also be used for the RootTransparent colorset option.
              Note: with a colorset background this command may add a lot of
              memory to the X server. For example, this adds the pixmap width
              times height bytes with a TiledPixmap image, screen_width times
              screen_height bytes with a Pixmap image or a C,B,D,R,S or Y
              Gradient and screen_width bytes with a VGradient or screen
              height bytes with an HGradient.

       *FvwmBacker: DoNotRetainPixmap
              Cancels the effect of the previous option. This is the default.

       It it possible to replace FvwmBacker's configuration at run-time,
       although it is not yet possible to remove existing configuration lines.
       This is done by simply removing the old configuration from within fvwm
       and then read a new one.  This can be done in many ways, for example by
       using an fvwm function or one of the modules FvwmCommand or


       DestroyModuleConfig FvwmBacker*
       *FvwmBacker: Command (Desk 0) -solid black
       *FvwmBacker: Command (Desk 1) -solid blue

       There is continued support for the now deprecated option:

       *FvwmBacker: Desk d command

              It is functionally equivalent to omitting the page coordinates
              with *FvwmBacker: Command:

              *FvwmBacker: Command (Desk Id) command

       The following are excerpts from an .fvwm2rc file which describe
       FvwmBacker initialization commands:

       # Set Up Backgrounds for different desktop pages (2 desks, 3x2 pages).
       *FvwmBacker: Command (Page 2 *) -solid steelblue
       *FvwmBacker: Command (Desk 0, Page 0 0) Exec fvwm-root $[HOME]/bg2.xpm
       *FvwmBacker: Command (Desk 0, Page 0 1) -solid midnightblue
       *FvwmBacker: Command (Desk 0, Page 1 *) -solid yellow
       *FvwmBacker: Command (Desk 1, Page * 0) -solid navy
       *FvwmBacker: Command (Desk 1, Page * 1) Colorset 5

       Mike Finger (mfinger@mermaid.micro.umn.edu)
                   (doodman on IRC, check the #linux channel)

Modified by
       Andrew Davison (davison@cs.monash.edu.au)

       Michael Han (mikehan@best.com)

       Mikhael Goikhman (migo@homemail.com)

3rd Berkeley Distribution  06 November 2016 (2.6.8)              FvwmBacker(1)