Le mardi 19 juin 2007 à 09:50 -0400, Alexandre Quessy a écrit : 
Hi all,
I was wondering if someone has an idea on how one could create a
switch to turn on and off an installation. I was thinking about either
a push button to turn it off, or a web interface. Maybe one of those
two things could make Pd (or PHP) write to a file that would be parsed
by a cron job every minute. That cron job should be owned by root in
order to be able to halt the computer. Then, to turn it on, I guess
one could set the bios to turn on the computer automagically when the
power gets down and then up again... Or one could use the computer
power button (but in this case, it is an laptop that I want to hide
deeply...) The whole idea behind this is to avoid to suddenly turn off
the computer, which would probably corrupt the file system at some
point. Of course I use GNU/Linux : probably Ubuntu Server or Debian.

Any suggestion ?
hi alex,

I lately setup a video installation using a Debian Lenny box on a mini-PC,  that's hidden in the ceiling because of noise and visual distrubance.
Of course the ACPI button is "very" difficult to reach,  Bios  has been setup to restart after a power failure. The power cord is over 10m long and connected to a switchable power adaptor.
Shell access is granted from the artist's laptop running windoze thanks to Putty.
Pd is started/stopped from the command line. The box is shutdown thanks to the magical "sudo halt" command line.

I used to connect that machine to an UPC, but never had enough time to have it commanded over serial port which a very good solution to both protect your machine from data loss and have it start/stop at will.

++
O.