If no specific client program is given on the command line, xinit will look for a file in the user's home directory called .xinitrc to run as a shell script to start up client programs. If no such file exists, xinit will use the following as a default:
xterm -geometry +1+1 -n login -display :0
If no specific server program is given on the command line, xinit will look for a file in the user's home directory called .xserverrc to run as a shell script to start up the server. If no such file exists, xinit will use the following as a default:
Note that this assumes that there is a program named X in the current search path. The site administrator should, therefore, make a link to the appropriate type of server on the machine, or create a shell script that runs xinit with the appropriate server.
Note, when using a .xserverrc script be sure to “exec” the real X server. Failing to do this can make the X server slow to start and exit. For example:
An important point is that programs which are run by .xinitrc should be run in the background if they do not exit right away, so that they don't prevent other programs from starting up. However, the last long-lived program started (usually a window manager or terminal emulator) should be left in the foreground so that the script won't exit (which indicates that the user is done and that xinit should exit).
An alternate client and/or server may be specified on the command line. The desired client program and its arguments should be given as the first command line arguments to xinit. To specify a particular server command line, append a double dash (--) to the xinit command line (after any client and arguments) followed by the desired server command.
Both the client program name and the server program name must begin with a slash (/) or a period (.). Otherwise, they are treated as an arguments to be appended to their respective startup lines. This makes it possible to add arguments (for example, foreground and background colors) without having to retype the whole command line.
If an explicit server name is not given and the first argument following the double dash (--) is a colon followed by a digit, xinit will use that number as the display number instead of zero. All remaining arguments are appended to the server command line.
Below is a sample .xinitrc that starts a clock, several terminals, and leaves the window manager running as the “last” application. Assuming that the window manager has been configured properly, the user then chooses the “Exit” menu item to shut down X.
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 & twm
Sites that want to create a common startup environment could simply create a default .xinitrc that references a site-wide startup file:
#!/bin/sh . /usr/local/lib/site.xinitrc
Another approach is to write a script that starts xinit with a specific shell script. Such scripts are usually named x11, xstart, or startx and are a convenient way to provide a simple interface for novice users:
#!/bin/sh xinit /usr/local/lib/site.xinitrc -- /usr/bin/X -br