FvwmButtons(1)

NAME
FvwmButtons - the FVWM buttonbox module

SYNOPSIS
FvwmButtons is spawned by fvwm, so no command line invocation will work.

DESCRIPTION
The FvwmButtons module provides a window of buttons which sits on the X terminal's root window. The user can press the buttons at any time, and trigger invocation of a user-specified command by the window manager. FvwmButtons only works when fvwm is used as the window manager. The buttonbox can be of any configuration or geometry, and can have monochrome or color icons to represent the actions which would be invoked.

INITIALIZATION
During initialization, FvwmButtons will search for a configuration file which describes the buttonbox geometry, color, icons, and actions. The format of this files will be described later. The configuration file will be the one which fvwm used during its initialization. To use FvwmButtons with several different configurations, you can invoke FvwmButtons with an optional parameter, which it will use as its name instead (e.g "Module FvwmButtons SomeButtons"). SomeButtons will then read only the lines in the configuration file starting with "*SomeButtons", and not the lines belonging to FvwmButtons. You can also specify an optional configuration file to use instead of the default fvwm configuration file, by giving a second argument which is a filename. This will override the setting "*FvwmButtonsFile", see below.

INVOCATION
FvwmButtons can be invoked by inserting the line 'Module FvwmButtons' in the .fvwmrc file. This should be placed in the InitFunction if FvwmButtons is to be spawned during fvwm's initialization, or can be bound to a menu or mouse button or keystroke to invoke it later. Fvwm will search directory specified in the ModulePath configuration option to attempt to locate FvwmButtons.

CONFIGURATION OPTIONS
The following options int the .fvwmrc file are understood by FvwmButtons:

*FvwmButtonsBack color
    Specifies the background color for the buttons. A relief and a shadow color will also be calculated from this.

*FvwmButtonsColumns columns
    Specifies the number of columns of buttons to be created. If unspecified, the number of columns will be set to the number of buttons requested, divided by the number of rows. If both the rows and columns are specified, but do not specify as many buttons as are defined, then the users columns specification will be ignored.

*FvwmButtonsFile filename
    Specifies that the configuration for this button is found in the file filename, which will have to be given with full pathname, or is assumed to be in fvwm's startup directory. The configuration file is in the same format as fvwm's configuration file, but each line is read as if prefixed by "*FvwmButtons". Comments are given by starting a line with "#", line continuation is done by ending a line with a "\".

*FvwmButtonsFont font
    Specifies the font to be used for labeling the buttons, or None.

*FvwmButtonsFore color
    Specifies the color used for button label text and monochrome icons.

*FvwmButtonsFrame width
    Specifies the width of the relief around each button. If this is given as a negative number, the relief will at all times be the inverse of the normal relief. In effect, you will get a sunken button, which is raised when activated.

*FvwmButtonsGeometry geometry
    Specifies the FvwmButtons window location. The size should not be specified, as FvwmButtons automatically chooses a size which gracefully accomodates all its buttons. The geometry is a standard X11 window geometry specification.

*FvwmButtonsPadding width height
    The amount of free space between the relief of the button and its contents is normally 2 pixels to the sides and 4 pixels above and below, except for swallowed windows and containers, which are not padded at all, unless given specific orders. This setting specifies the default horizontal padding to be width pixels, and the vertical padding to be height pixels.

*FvwmButtonsRows rows
    Specifies the number of rows of buttons to be created. If unspecified, 2 rows will be used.

*FvwmButtons(options) [title icon command]
    Specifies the contents of a button in the buttonbox. The following options, separated by commas or whitespace, can be given a button:

widthxheight
    The button will be width times the normal button width and height times the normal button height.

Action [(options)] command
    Specifies an fvwm command to be executed when the button is activated by pressing return or a mouse button. If command contains whitespace it must be quoted. The current options are: Mouse n - this action is only executed for mouse button n. One actions can be defined for each mouse button, in addition to the general action.

Back color
    Specifies the background color to be used drawing this box. A relief color and a shadow color will also be calculated from this.

Container [(options)]
    Specifies that this button will contain a miniature buttonbox, more or less equivalent to swallowing another FvwmButtons module. The options are the same as can be given for a single button, but they affect all the contained buttons. Options available for this use are Back, Font, Fore, Frame and Padding. Flags for Title and Swallow options can be set with Title(flags) and Swallow(flags. You should also specify either "Columns width" or "Rows height", or "Rows 2" will be assumed for purpose of arranging the buttons inside the container. For an example, see the Sample configuration section. The container button itself (separate from the contents) can take format options like Frame and Padding, and commands can be bound to it. This means you can make a sensitive relief around a container, like
      *FvwmButtons(2x2, Frame 5, Padding 2 2, Action Beep,\
          Container(Frame 1)) Typically you will want to at least give the container a size setting widthxheight.

End Specifies that no more buttons are defined for the current container, and further buttons will be put in the container's parent. This option should be given on a line by itself, i.e
      *FvwmButtons(End)

Font fontname
    Specifies that the font fontname is to be used for labeling this button.

Fore color
    Specifies a color of the title and monochrome icons in this button.

Frame width
    The relief of the button will be width pixels wide. If width is given as a negative number, the relief will at all times be the inverse of the normal relief. In effect, you will get a sunken button, which is raised when activated.

Icon filename
    The name of an X11 bitmap file or XPM color icon file, containing the icon to display on the button. FvwmButtons will search through the path specified in the fvwm IconPath or PixmapPath configuration items to find the icon file.

NoSize
    This option specifies that this button will not be considered at all when making the initial calculations of buttonsizes. Useful for the odd button that gets just a couple of pixels to large to keep in line, and therefor blows up your whole buttonbox. "NoSize" is equivalent to "Size 0 0".

Padding width height
    The amount of free space between the relief of the button and its contents is normally 2 pixels to the sides and 4 pixels above and below, except for swallowed windows and containers, which are by default not padded at all. This option sets the horizontal padding to width and the vertical padding to height.

Size width height
    Specifies that the contents of this button will require width by height pixels, regardless of what size FvwmButtons calculates from the icon and the title. A buttonbar with only swallowed windows will not get very large without this option specified, as FvwmButtons does not consider sizes for swallowing buttons. Note that this option gives the minimum space assured; other buttons might require the buttonbox to use larger sizes.

Swallow [(flags)] hangon command
    Causes FvwmButtons to execute command, and when a window matching the name hangon appears, it is captured and swallowed into this button. An example:
      *FvwmButtons(Swallow XClock 'Exec xclock &') will take the first window whose name, class or resource is "XClock" and display it in the button. Modules can be swallowed by specifying the module instead of 'Exec whatever', like:
      *FvwmButtons(Swallow "FvwmPager" "FvwmPager 0 0") The flags that can be given to swallow are: NoClose / Close - Specifies whether the swallowed program in this button will be unswallowed or closed when FvwmButtons exit cleanly. "NoClose" can be combined with "UseOld" to have windows survive restart of windowmanager. The default setting is "Close". NoHints / Hints - Specifies whether hints from the swallowed program in this button will be ignored or not, useful in forcing a window to resize itself to fit its button. The default value is "Hints". NoKill / Kill - Specifies whether the swallowed program will be closed by killing it or by sending a message to it. This can be useful in ending programs that doesn't accept window manager protocol. The default value is "NoKill". This has no effect if "NoClose" is specified. NoRespawn / Respawn - Specifies whether the swallowed program is to be respawn if it dies. If "Respawn" is specified, the program will be respawned using the original command. Use this option with care, the program might have a very legitimate reason to die. NoOld / UseOld - Specifies whether the button will try to swallow an existing window matching the hangon name before spawning one itself with command. The default value is "NoOld". "UseOld" can be combined with "NoKill" to have windows survive restart of windowmanager. If you want FvwmButtons to swallow an old window, and not spawn one itself if failing, let the command be "Nop":
      *FvwmButtons(Swallow (UseOld) "Console" Nop) If you want to be able to start it yourself, combine it with an action:
      *FvwmButtons(Swallow (UseOld) "Console" Nop, \
                   Action `Exec "Console" console &`) NoTitle / UseTitle - Specifies whether the title of the button will be taken from the swallowed window's title or not. If "UseTitle" is given, the title on the button will change dynamically to reflect the window name. The default is "NoTitle".

Title [(options)] name
    Specifies the title which will be written on the button. Whitespace can be included in the title by quoting it. If a title at any time is to long for its buttons, characters are chopped of one at a time until it fits. If justify is "Right", the head is removed, otherwise its tail is removed. These options can be given to Title: Center - The title will be centered horizontally. This is the default. Left - The title will be justified to the left side. Right - The title will be justified to the right side. Side - This will cause the title to appear on the right hand side of any icon or swallowed window, instead of below it which is the default. If you use small icons, and combine this with the "Left" option, you can get a look similar to fvwm's menus.

Legacy fields [title icon command]
    These fields are kept for compatibility with previous versions of FvwmButtons, and their use is discouraged. The title field is similar to the option Title name. If the title field is "-", no title will be displayed. The icon field is similar to the option Icon filename. If the icon field is "-" no icon will be displayed. The command field is similar to the option Action command or alternatively Swallow "hangon" command.

The command
    Any fvwm command is recognized by FvwmButtons. See fvwm(1) for more info on this. The Exec command has a small extension when used in Actions, its syntax is here:
      Exec ["hangon"] command When FvwmButtons finds such an Exec command, the button will remain pushed in until a window whose name or class matches the qouted portion of the command is encountered. This is intended to provide visual feedback to the user that the action he has requested will be performed. If the qouted portion contains no characters, then the button will pop out immediately. Note that users can continue pressing the button, and re-executing the command, even when it looks "pressed in."

Quoting
    Any string which contains whitespace must be quoted. This include commands. Quoting can be done with any of the three quotation characters; single quote:
      'This is a "quote"', double quote:
      "It's another `quote'", and backquote:
      `This is a strange quote`. The backquoting is purposeful if you use a preprocessor like FvwmCpp and want it to get into your commands, like this:
      #define BG gray60
      *FvwmButtons(Swallow "xload" `Exec xload -bg BG &`)

ARRANGEMENT ALGORITHM
FvwmButtons tries to arrange its buttons as best it can, by using recursively, on each container including the buttonbox itself, the following algorithm.

Getting the size right
    First it calculates the number of button unit areas it will need, by adding the width times the height in buttons of each button. Containers are for the moment considered a normal button. Then it considers the given rows and columns arguments. If the number of rows is given, it will calculate how many columns are needed, and stick to that, unless columns is larger, in which case you will get some empty space at the bottom of the buttonbox. If the number of columns is given, it calculates how many rows it needs to fit all the buttons. If neither is given, it assumes you want two rows, and finds the number of columns from that.

Shuffling buttons
    Now it has a large enough area to place the buttons in, all that is left is to place them right. The algorithm assumes the buttons are all of unit size, and places them in a left to right, top to bottom western fashion. Then it looks at button 1, and considers: Is this button larger than normal? If it isn't, the same thing is done for the next buttons. When a button is found that is larger than 1x1, space must be provided for it. The algorithm assumes it is in the right coordinate, its upper left corner should be unchanged. It then "slides" away the buttons that occupies the places needed for this button. The buttons are slid to the right, wrapping around to the next line. When all the space has been cleared for this button the algorithm continues with the next button, doing the same.

Containers
    Containers are arranged by the same algorithm, in fact they are shuffled recursively as the algorithm finds them.

Clarifying example
    An example might be useful here: Suppose you have 6 buttons, all unit sized except number two, which is 2x2. This makes for 5 times 1 plus 1 times 4 equals 9 unit buttons total area. Assume you have requested 3 columns.

    1) +---+---+---+   2) +---+---+---+   3) +---+---+---+
       | 1 | 2 | 3 |      | 1 | 2 |   |      | 1 | 2 |   |
       +---+---+---+      +---+---+---+      +---+---+---+
       | 4 | 5 | 6 |      | 3 | 4 | 5 |      | 3 |   | 4 |
       +---+---+---+      +---+---+---+      +---+---+---+
       |           |      | 6 |       |      | 5 | 6 |   |
       +-----------+      +---+-------+      +---+---+---+
    4) +---+---+---+   5) +---+-------+
       | 1 | 2 |   |      | 1 |       |
       +---+---+---+      +---+   2   |
       | 3 |   |   |      | 3 |       |
       +---+---+---+      +---+---+---+
       | 4 | 5 | 6 |      | 4 | 5 | 6 |
       +---+---+---+      +---+---+---+

    The algorithm starts as in figure 1. The first large button it finds is number 2, and it will try to free up each of the unit areas it occupies, in a left to right, top to bottom order. First it sees that button 3 is in its way, and it shifts all the buttons, giving figure 2. Now it finds that button 4 is in the way, so button 4 to 6 are shifted, yielding figure 3. Button 4 is still barring progress, so it shifts button 4 to 6 once more, ending up at figure 4. Now all the button units required by button 2 are freed, and button 2 can be given its real size.

What size will the buttons be?
    When FvwmButtons has read the icons and fonts that are required by its configuration, it can find out which size is needed for every non-swallowing button. The unit button size of a container is set to be large enough to hold the largest button in it without squeezing it. Swallowed windows are simple expected to be comfortable with the buttonsize they get from this scheme. If a particular configuration requires more space for a swallowed window, it can be set in that button's configuration line using the option "Size width height". This will tell FvwmButtons to give this button at least width by height pixels inside the relief and padding.

SAMPLE CONFIGURATION
The following are excepts from a .fvwmrc file which describe FvwmButtons initialization commands:

##########################################################
# Load any modules which should be started during fvwm
# initialization
ModulePath /usr/lib/X11/fvwm:/usr/bin/X11
# Make sure FvwmButtons is always there.
AddToFunc InitFunction     "I" Module FvwmButtons
AddToFunc RestartFunction  "I" Module FvwmButtons
# Make it titlebar-less, sticky, and give it an icon
Style "FvwmButtons"	Icon toolbox.xpm, NoTitle, Sticky
##########################################################
*FvwmButtonsFore Black
*FvwmButtonsBack rgb:90/80/90
*FvwmButtonsGeometry -135-5
*FvwmButtonsRows 1
*FvwmButtonsFont -*-helvetica-medium-r-*-*-12-*
*FvwmButtonsPadding 2 2
*FvwmButtons(Title Resize,Icon resize.xpm ,Action Resize)
*FvwmButtons(Title Move  ,Icon arrows2.xpm,Action Move  )
*FvwmButtons(Title Lower ,Icon Down       ,Action Lower )
*FvwmButtons(Title Raise ,Icon Up         ,Action Raise )
*FvwmButtons(Title Kill  ,Icon bomb.xpm   ,Action Destroy)
*FvwmButtons(1x1,Container(Rows 3,Frame 1))
*FvwmButtons(Title Dopey ,Action \
    `Exec "big_win" xterm -T big_win -geometry 80x50 &`)
*FvwmButtons(Title Snoopy, Font fixed, Action \
    `Exec "small_win" xterm -T small_win &`)
*FvwmButtons(Title Smokin')
*FvwmButtons(End)
*FvwmButtons(Title Xcalc, Icon rcalc.xpm,\
             Action `Exec "Calculator" xcalc &`)
*FvwmButtons(Title XMag, Icon magnifying_glass2.xpm,\
             Action `Exec "xmag" xmag &`)
*FvwmButtons(Title Mail, Icon mail2.xpm,\
             Action `Exec "xmh" xmh &`)
*FvwmButtons(4x1, Swallow "FvwmPager" `FvwmPager 0 3`\
             Frame 3)
*FvwmButtons(Swallow(UseOld,NoKill) "xload15" `Exec xload\
     -title xload15 -nolabel -bg rgb:90/80/90 -update 15 &`)

The last lines are a little tricky - one spawns an FvwmPager module, and captures it to display in a quadruple width button. is used, the Pager will be as big as possible within the button's relief. The final line is even more magic. Note the combination of UseOld and NoKill, which will try to swallow an existing window with the name "xload15" when starting up (if failing: starting one with the specified command), which is unswallowed when ending FvwmButtons. The color specification rgb:90/80/90 is actually the most correct way of specifying independent colors in X, and should be used instead of the older #908090. If the latter specification is used in your configuration file, you should be sure to escape the hash in any of the commands which will be executed, or fvwm will consider the rest of the line a comment.

COPYRIGHTS
The FvwmButtons program, and the concept for interfacing this module to the Window Manager, are all original work by Robert Nation Copyright 1993, Robert Nation. No guarantees or warranties or anything are provided or implied in any way whatsoever. Use this program at your own risk. Permission to use this program for any purpose is given, as long as the copyright is kept intact. Further modifications and patching by Jarl Totland, copyright 1996. The statement above still applies.

AUTHOR
Robert Nation. Somewhat enhanced by Jarl Totland.