The script will work in both 2.6.24 and 2.6.25, so without further ado, here it is. It is written as a function for easy inclusion in any prompts.

#!/bin/zsh 
bat() {
PROC=/proc/acpi/battery/BAT0
SYS=/sys/class/power_supply/BAT0/uevent
STATE=
# dc: design capacity, rc: remaining capacity
if [ -f $PROC/info ]; then
    STATE=$PROC/state   # 2.6.24
    dc=$(grep 'last full' < $PROC/info | awk '{ print $4 }')
    rc=$(grep 'remaining' < $PROC/state | awk '{ print $3 }')
elif [ -f $SYS ]; then
    STATE=$SYS          # 2.6.25
    dc=$(grep '\<POWER_SUPPLY_CHARGE_FULL\>' < $SYS | awk -F= '{ print $2 }')
    rc=$(grep '\<POWER_SUPPLY_CHARGE_NOW\>' < $SYS | awk -F= '{ print $2 } ')
else
    exit
fi
p=$(echo 3k $rc $dc / 100 \* p | dc )

if grep -iq discharging $STATE; then
    printf " %02d" "$p"
else
    if [ ${p%.*} -lt 100 ]; then
    printf " %02d+" "$p"
    fi
fi
}
bat

Update

Ton Kersten has an even better one which saves a few greps.

#!/bin/zsh 
bat() {
PROC=/proc/acpi/battery/BAT0
SYS=/sys/class/power_supply/BAT0/uevent
STATE=
# dc: design capacity, rc: remaining capacity                                                                           
if [ -f $PROC/info ]
then
    STATE=$PROC/state   # 2.6.24
    dc=$(awk '/last full/ { print $4 }' $PROC/info)
    rc=$(awk '/remaining/ { print $3 }' $PROC/state)
elif [ -f $SYS ]
then
    STATE=$SYS          # 2.6.25
    dc=$(awk -F= '$1 ~ /^POWER_SUPPLY_CHARGE_FULL$/ { print $2 }' $SYS)
    rc=$(awk -F= '$1 ~ /^POWER_SUPPLY_CHARGE_NOW$/  { print $2 }' $SYS)
else
    return 0
fi

p=$(echo 3k $rc $dc / 100 \* p | dc )

if grep -iq discharging $STATE; then
    printf " %02d" "$p"
else
    if [ ${p%.*} -lt 100 ]; then
    printf " %02d+" "$p"
    fi
fi
}
bat

Update 2

Just found that there is also a nice tool, called acpi...which makes it even more easy:

% acpi -V
Battery 0: Full, 100%
AC Adapter 0: on-line
Thermal 0: ok, 53.0 degrees C
Cooling 0: Processor 0 of 7

Completely inspired by localepurge (and I stole some code from it).

But I wanted to purge stuff in /usr/share/doc/$package too as this takes too much disk space on my precious (talking about the EeePC here). If I really need the documentation I will also install the package on my server and look at it there.

localepurge consists out of two important parts, a hook for dpkg which is called after each installation. This hook is placed in /etc/apt/apt.conf.d. And a script that will actually remove the locales (/usr/sbin/localepurge).

For my needs a actually need to tweak the hook a little and write a little script. My first thought was to actually look at the package being installed and only remove the doc-dir for that package, but a quick search yielded no clue on how to give the name of the package to DPkg::Post-Invoke. So the next best thing I could come up with was to delete everything in /usr/share/doc every time.

DPkg::Post-Invoke

The Post-Invoke from localepurge looks like this:

DPkg
{
Post-Invoke {"if [ -x /usr/sbin/localepurge ] && [ $(ps w -p "$PPID"
    | grep -c remove) != 1 ]; then /usr/sbin/localepurge; else exit 0; fi";};
};

This needs to be tweaked a little for my purposes. I'm storing the scripts in the dir /home/miekg/bin -- as I'm the sole user of my EeePC.

DPkg
{
Post-Invoke {"if [ -x /home/miekg/bin/docpurge ] && [ $(ps w -p "$PPID"
    | grep -c remove) != 1 ]; then /home/miekg/bin/docpurge; else exit 0; fi";};
};

Save this file in /etc/apt/apt.conf.d as 99-docpurge.

docpurge

I've named my script docpurge and its a stupid script that just deletes stuff in /usr/share/doc. For completeness here it is:

#!/bin/bash
# delete stuff in /usr/share/doc

DOCDIR=/usr/share/doc
for i in $DOCDIR/*; do
rm -rf $i
done

suspend script

I want my suspend to work, but every time I suspended xfdesktop crashed. Turns out this is due to the stopping of dbus. I've modified the suspend script to not meddle with dbus. This seemed to have fixed this particular issue. I've also added an:

fuser -k /media/disk    # kill all users of /media/disk
umount /dev/sdb1        # now it can be umounted

to the script. This unmounts the disk on suspend. I'm now letting xfdesktop (re)mount /dev/sdb1 on resume. This works fine.

mpd

Install mpd, and make a symlink from /var/lib/mpd/music to /media/disk/music. /media/disk is the spot where the SD disk is mounted by xfdesktop.

The problem with mpd is that is will not start if it cannot find its music directory. With this symlink trick, this directory is always there even if the mounting of /dev/sdb1 went wrong.

Also modify /etc/mpd.conf to comment out bind_to_address by putting a # in front of that line. Next restart mpd: /etc/init.d/mpd restart

mpc

mpc rocks. Actually I only need gmpc to load the playlist in mpd. From then on I use mpc: mpc next, mpc play, etc. Real easy from the cmdline; mpc update also rocks.

Now I just plugin my headset, start the music and start compiling and writing software in the train.

The EeePC really rocks!

I'm using zsh here, but this script will work in any shell. I'm putting the output of the script on the right side of my prompt in a subdewed grey color. It adds a + on the right when it is charging.

script

#!/bin/zsh
dc=$(cat /proc/acpi/battery/BAT0/info | grep 'last full' | awk ' { print $4 }')
rc=$(cat /proc/acpi/battery/BAT0/state | grep 'remaining' | awk ' { print $3 } ')

p=$(echo 3k $rc $dc / 100 \* p | dc ) 
if grep -q discharging /proc/acpi/battery/BAT0/state; then
    printf "%02d" "$p"
else
    printf "%02d+" "$p"
fi

xbattbar-acpi

xbattbar-acpi is Anothor tool you will need. It will display a small bar at the bottom of your (X) screen, showing the remaining capacity. It keeps out of your way, uses only 3 pixels and works just like the script above.