Basic fvwm Configuration

This article will attempt to introduce you to one of the most versatile and popular X-Windows managers: fvwm (which, I've been told, originally stood for “Frugal Virtual Window Manager”).
Getting Things Going

Now that you've copied the .fvwmrc file to your home directory and decided how you'll track your changes to it, you're ready to start tinkering! One of the first things you might be interested in is automatically launching programs when fvwm starts. You may want to start an xterm or two, a clock or calendar, xbiff (to warn you when mail arrives), and so forth. fvwm allows you to define an InitFunction within .fvwmrc that handles program launching at initialization. Before discussing this, however, we need to briefly mention xinit.

xinit is the program responsible for starting the X Window System and, like fvwm, it uses an .xinitrc file. A user may create a personalized copy of this file in her or his home directory as ~/.xinitrc, or simply use the system wide default located in /usr/lib/X11/xinit/xinitrc. To see how xinit launches programs at startup, let's look at the default xinitrc file that came with Slackware 2.2.0:

# start some nice programs
xsetroot -solid SteelBlue &

In this simple example, xsetroot sets the color of the root window to SteelBlue. Once it is done, fvwm is started. A slightly more complicated example is given in the manual page for xinit:

xrdb -load $HOME/.Xresources
xsetroot -solid gray &
xclock -g 50x50-0+0 -bw 0 &
xload -g 50x50-50+0 -bw 0 &
xterm -g 80x24+0+0 &
xterm -g 80x24+0-0 &

In this example, several programs are launched before twm is started. The important thing to point out is that the stanzas which launch programs, such as xclock and the xterm, need to end with an ampersand (&) so as to have them running in the background. It is also important that the window manager be started last and that it runs in the foreground (i.e., do not add an ampersand at the end of the line).

fvwm provides a similar method for launching programs at startup using the InitFunction. To see how, let's look at a sample entry in .fvwmrc:

Function "InitFunction"
# Module  "I"  FvwmBanner
# Get the fvwm GoodStuff button bar running
  Module  "I"  GoodStuff
# Module  "I"  FvwmPager 0 3
# Then, the analog clock - Swallowed by GoodStuff
  Exec  "I"  exec xclock -g 140x160-145+138 &
  Wait  "I"  xclock
# Start xmailbox - swallowed by GoodStuff
  Exec  "I"  exec xmailbox &
  Wait  "I"  xmailbox
# Fire up xload - also swallowed by GoodStuff
  Exec  "I"  exec xload -geometry 80x80+100+100 &
  Wait  "I"  xload
# Now, start up xcalendar
  Exec  "I"  exec xcalendar -g 345x382+793+372 &
  Wait  "I"  xcalendar
# Finally, fire up a full screen xterm
  Exec  "I"  exec xterm -sb -j -ls -g 84x48+4+4 &
  Wait  "I"  xterm

Since it's easiest to explain by example, let's see what you'd need to do to add a second xterm to the startup. To begin with, InitFunction generally uses two-line stanzas for launching programs, and these take the form:

  Exec  "I"  exec program_name -options &
  Wait  "I"  program_title

For example, the stanzas which start xcalendar look like:

# Now, start up xcalendar
  Exec  "I"  exec xcalendar -g 345x382+793+372 &
  Wait  "I"  xcalendar

Lines which begin with the hash (#) character are treated as comments and ignored by fvwm. The first line begins with the reserved word Exec and has four arguments:

1. An "I" (in double quotes).

2. The word exec.

3. The command used to start the program.

4. Any command line options followed by an ampersand (&).

The next line begins with the word Wait which causes an fvwm function to pause while a window with the name given on the command line is drawn to the display. In this case, the InitFunction pauses while a window with the title xcalendar is drawn to the display. Once the window has been drawn, fvwm continues.

Be aware that this is a bit of a fib, but a useful one for the moment. The Wait function is primarily used when programs are launched on more than one desktop—something we won't touch on for the moment. Assuming you use a single desktop, as in this present example, the Wait stanza may be safely omitted.

Going back to our assignment to start another xterm, we could launch a second xterm by adding the following:

  Exec  "I"  exec xterm &
  Wait  "I"  xterm

which would be sufficient to get a second xterm going.

If you added this entry and started fvwm, you'd find that when fvwm got to the point in the initialization process where the second xterm was started, it would draw the outline of the xterm window and wait for you to position it before proceeding. That's not very convenient if you have to do this every time fvwm starts. The way around this is to add a command line option specifying the xterm's geometry, which allows you to control where to place the window from the command line.


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