Manual: Fvwm2Backer

FvwmBacker(1)						Fvwm Modules					       FvwmBacker(1)

NAME
       FvwmBacker - the fvwm background changer module

SYNOPSIS
       Module FvwmBacker

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

DESCRIPTION
       The FvwmBacker module provides functionality to change the background when changing desktops.  Any command can be ex‐
       ecuted  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.

COPYRIGHTS
       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.

INITIALIZATION
       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.

INVOCATION
       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.

CONFIGURATION OPTIONS
       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  back‐
	      ground 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.

RUN-TIME CONFIGURATION
       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  FvwmCon‐
       sole.

       Example:

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

OLD-STYLE OPTIONS
       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

SAMPLE CONFIGURATION
       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

AUTHOR
       Mike Finger (mfinger@mermaid.micro.umn.edu)
		   (Mike_Finger@atk.com)
		   (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			   19 October 2022 (2.7.0)				       FvwmBacker(1)