I have searched around a bit for this and can't seem to find anything helpful.
I have my PC running Ubuntu 12.10 set up to suspend after 30 minutes of inactivity. I don't want to change that, it works great most of the time.
What I do want to do is disable the automatic suspend if a particular application is running. How can I do this?
The closest thing I've found so far is to add a shell script in /usr/lib/pm-utils/sleep.d which checks if the application is running and returns 1 to indicate that suspend should be prevented. But it looks like the system then gives up on suspending automatically, instead of trying again after another 30 minutes. (As far as I can tell, if I move the mouse, that restarts the timer again.) It's quite likely the application will finish after a couple of hours, and I'd rather my PC then suspended automatically if I'm not using it at that point. (So I don't want to add a call to pm-suspend when the application finishes.)
Is this possible?
EDIT: As I noted in one of the comments below, what I actually wanted was to inhibit suspend when my PC was serving files over NFS; I just wanted to focus on the "suspend" part of the question because I already had an idea how to solve the NFS part. Using the 'xdotool' idea given in one of the answers, I have come up with the following script which I run from cron every few minutes. It's not ideal because it stops the screensaver kicking in as well, but it does work. I need to have a look at why 'caffeine' doesn't correctly re-enable suspend later on, then I could probably do better. Anyway, this does seem to work, so I'm including it here in case anyone else is interested.
#!/bin/bash
# If the output of this function changes between two successive runs of this
# script, we inhibit auto-suspend.
function check_activity() {
/usr/sbin/nfsstat --server --list
}
# Prevent the automatic suspend from kicking in.
function inhibit_suspend() {
# Slightly jiggle the mouse pointer about; we do a small step and
# reverse step to try to stop this being annoying to anyone using the
# PC. TODO: This isn't ideal, apart from being a bit hacky it stops
# the screensaver kicking in as well, when all we want is to stop
# the PC suspending. Can 'caffeine' help?
export DISPLAY=:0.0
xdotool mousemove_relative --sync -- 1 1
xdotool mousemove_relative --sync -- -1 -1
}
LOG="$HOME/log/nfs-suspend-blocker.log"
ACTIVITYFILE1="$HOME/tmp/nfs-suspend-blocker.current"
ACTIVITYFILE2="$HOME/tmp/nfs-suspend-blocker.previous"
echo "Started run at $(date)" >> "$LOG"
if [ ! -f "$ACTIVITYFILE1" ]; then
check_activity > "$ACTIVITYFILE1"
exit 0;
fi
/bin/mv "$ACTIVITYFILE1" "$ACTIVITYFILE2"
check_activity > "$ACTIVITYFILE1"
if cmp --quiet "$ACTIVITYFILE1" "$ACTIVITYFILE2"; then
echo "No activity detected since last run" >> "$LOG"
else
echo "Activity detected since last run; inhibiting suspend" >> "$LOG"
inhibit_suspend
fi
EDIT 2: The script above works but thanks to another comment below, I am now using this pair of scripts, which have the advantage of allowing the screensaver to kick in while I am inhibiting suspend. The first is /usr/lib/pm-utils/sleep.d/000nfs-inhibit, which will prevent a suspend attempt if an inhibit file exists:
#!/bin/sh
LOG="/home/zorn/log/nfs-suspend-blocker.log"
INHIBITFILE="/home/zorn/tmp/nfs-suspend-blocker.inhibit"
echo "$0: Started run at $(date), arguments: $*" >> "$LOG"
if [ "$1" = "suspend" ] && [ -f "$INHIBITFILE" ]; then
echo "$0: Inhibiting suspend" >> "$LOG"
exit 1
fi
exit 0
The second is a modified version of the previous nfs-suspend-blocker script and should still be run from cron. It now follows the strategy outlined in the comment below:
```bash
#!/bin/bash
# This works in tandem with /usr/lib/pm-utils/sleep.d/000nfs-inhibit, which
# will prevent a suspend occurring if $INHIBITFILE is present. Once it prevents
# a suspend, it appears that it requires some "user activity" to restart the
# timer which will cause a subsequent suspend attempt, so in addition to
# creating or removing $INHIBITFILE this script also jiggles the mouse after
# removing the file to restart the timer.
# If the output of this function changes between two successive runs of this
# script, we inhibit auto-suspend.
function check_activity() {
/usr/sbin/nfsstat --server --list
}
# Slightly jiggle the mouse pointer about; we do a small step and reverse step
# to try to stop this being annoying to anyone using the PC.
function jiggle_mouse() {
export DISPLAY=:0.0
xdotool mousemove_relative --sync -- 1 1
xdotool mousemove_relative --sync -- -1 -1
}
LOG="$HOME/log/nfs-suspend-blocker.log"
ACTIVITYFILE1="$HOME/tmp/nfs-suspend-blocker.current"
ACTIVITYFILE2="$HOME/tmp/nfs-suspend-blocker.previous"
INHIBITFILE="$HOME/tmp/nfs-suspend-blocker.inhibit"
echo "$0: Started run at $(date)" >> "$LOG"
if [ ! -f "$ACTIVITYFILE1" ]; then
check_activity > "$ACTIVITYFILE1"
exit 0;
fi
/bin/mv "$ACTIVITYFILE1" "$ACTIVITYFILE2"
check_activity > "$ACTIVITYFILE1"
if cmp --quiet "$ACTIVITYFILE1" "$ACTIVITYFILE2"; then
echo "$0: No activity detected since last run" >> "$LOG"
if [ -f "$INHIBITFILE" ]; then
echo "$0: Removing suspend inhibit file and jiggling mouse" >> "$LOG"
/bin/rm "$INHIBITFILE"
jiggle_mouse
fi
else
echo "$0: Activity detected since last run; inhibiting suspend" >> "$LOG"
touch "$INHIBITFILE"
fi
