Re: [off-topic] How to auto-run xlock?

["E.L. Meijer \(Eric\)" <tgakem@sg10.chem.tue.nl>]

> 
> 
> I have a program that I want to run only while my PC is unattended. I
> don't need the screen locked necessarily.
> 
> xlock does this for me:
> 
> xlock +nolock -startCmd startsetiathome -mode blank
> 
> but I have to run it manually. When I log back in, it does kill the
> running command (startsetiathome) just like I want.
> 
> I'd like this exact behaviour but somehow I need xlock to always be
> running, waiting to jump in after the idle period.

I thought about this problem before, and now realised you can check
keyboard and mouse activity looking at /proc/interrupts.  You could then
start a script like this in your .xsession file (adapt the variables at
the start to your needs):

runsaver:
------------------------------------------------------------------------
#! /bin/sh

# these are the interrupts of your keyboard and mouse,
# check out your /proc/interrupts:
INTERRUPTS="1 4"
        
# this is the interval in seconds between checks of /proc/interrupts
SLEEPTIME=30

# if more than MAXINTERVALS * SLEEPTIME seconds pass without activity,
# the xlock program will run
MAXINTERVALS=10

# command line options for xlock
XLOCKFLAGS="-nolock -mode bat"

checkactive () {
  TOTALS=""
  INTERVALS=0 
  while true; do
    OLDTOTALS=$TOTALS
    TOTALS=""
    for x in $INTERRUPTS; do
      TOTALS="$TOTALS `grep "\<$x:" /proc/interrupts | \
                       sed -e 's/^.*: *\([0-9]*\).*/\1/'`"
    done
    if [ "$TOTALS" = "$OLDTOTALS" ]; then
      INTERVALS=`expr $INTERVALS + 1`
      if [ $INTERVALS -ge $MAXINTERVALS ]; then
        break
      fi
    else
      INTERVALS=0
    fi
    sleep $SLEEPTIME
  done
}

while true; do
  checkactive
  xlock $XLOCKFLAGS
done

------------------------------------------------------------------------

Note I have only just barely tested this.

> If anyone is interested, the program that I'm running is the SETI at Home
> client. SETI is "The Search for Extraterrestrial Intelligence".

Great, sent my regards to the aliens once you find them :)

HTH,
Eric

-- 
 E.L. Meijer (tgakem@chem.tue.nl)
 Eindhoven Univ. of Technology
 Lab. for Catalysis and Inorg. Chem. (SKA)