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(gpm.info)Special Commands

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Special Commands
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   Version 1.10 adds the capability to execute _special_ commands on
certain circumstances. Special commands default to rebooting and halting
the system, but the user can specify his/her personal choice. The
capability to invoke commands using the mouse is a handy one for
programmers, because it allows to issue a clean shutdown when the
keyboard is locked and no network is available to restore the system to
a sane state.

   Special commands are toggled by triple-clicking the left and right
button - an unlikely event during normal mouse usage. The easiest way
to triple-click is pressing one of the buttons and triple-click the
other one. When special processing is toggled, a message appears on the
console (and the speaker beeps twice, if you have a speaker); if the
user releases all the buttons and presses one of them again within
three seconds, then the special command corresponding to the button is
executed.

   The default special commands are:

LEFT BUTTON
     Reboot the system by signalling the init process

MIDDLE BUTTON (IF ANY)
     Execute `/sbin/shutdown -h now'

RIGHT BUTTON
     Execute `/sbin/shutdown -r now'

   The `-S' command line switch enables special command processing and
allows to change the three special commands. To accept the default
commands use `-S ""' (i.e., specify an empty argument).  To specify
your own commands, use a colon-separated list to specify commands
associated to the left, middle and right button. If any of the commands
is empty, it is interpreted as `send a signal to the init process'. This
particular operation is supported, in addition to executing external
commands, because sometimes bad bugs put the system to the impossibility
to fork; in these rare case the programmer should be able to shutdown
the system anyways, and killing init from a running process is the only
way to do it.

   As an example, `-S ":telinit 1:/sbin/halt"', associates killing init
to the left button, going single user to the middle one, and halting
the system to the right button.

   System administrators should obviously be careful about special
commands, as gpm runs with superuser permissions. Special commands are
best suited for computers whose mouse can be physically accessed only by
trusted people.