HowTo: Beep internal PC speaker on usb hotplug

[chewearn]

A. Introduction

I came upon this page when playing around with a Linksys NSLU2. After understanding the script at the bottom of that page, it occurred to me that I could do something similar for an Ubuntu PC. Wouldn't it be nice for the PC speaker to beep when you plug/unplug a USB device? I went about modifying the script to make a simpler one for beeping the internal PC speaker in Ubuntu.

Note: I am referring to the internal PC speaker, not the audio output from the sound card.



B. Prerequisite

Tested OK in the following systems:
1. Ubuntu Intrepid 8.10 86_x64
2. Ubuntu Hardy 8.04 86_x64
3. Ubuntu Hardy 8.04 i386
4. Ubuntu Gutsy 7.10 i386

The following steps rely on the terminal. Open a terminal window by:
Panel menu > Application > Accessories > Terminal

Then, copy/paste the codes for each of the steps.



C. Install


1. Install beep

This will install the beep program, that will emit the sound from the PC speaker.

sudo apt-get install beep

.

2. Test beep

beep

You should hear a beep from the PC speaker.


3. Create the script file

cd ~

cat > usb-hotplug.sh << "EOF"
#!/bin/bash

LOCKFILE="/tmp/usb-hotplug.lock"

# Lock to convert multiple triggers to single run
if ( set -o noclobber; echo "$$" > "$LOCKFILE" ) 2> /dev/null; then
    trap 'rm -f "$LOCKFILE"; exit $?' INT TERM EXIT

    BEEP="/usr/bin/beep"
    STATFILE="/tmp/whatisinusb"
    CURR=`lsusb`
    PREV=`cat $STATFILE`

    if [ "${#CURR}" -gt "${#PREV}" ] ; then
        $BEEP -l 100 -f 2000 -n -l 150 -f 3000
    fi

    if [ "${#CURR}" -lt "${#PREV}" ] ; then
        $BEEP -l 100 -f 3000 -n -l 150 -f 2000
    fi

    if [ "$CURR" != "$PREV" ] ; then
        echo "$CURR" > $STATFILE
    fi

    rm -f "$LOCKFILE"
    trap - INT TERM EXIT
fi

EOF

.

4. Move the script to /bin

sudo cp ~/usb-hotplug.sh /bin/usb-hotplug.sh

.

5. Make the script executable

sudo chmod +x /bin/usb-hotplug.sh

.

6. Add udev rule to trigger the script upon an usb hotplug event

echo BUS==\"usb\", RUN+=\"/bin/usb-hotplug.sh\" | sudo tee -a /etc/udev/rules.d/80-programs.rules

.


C. End notes

That's it! It should work immediately, without any reboot.



D. Uninstall

If you find the beepings irritating after a while, you can remove it by:


1. Remove the udev rule

Fire-up a text editor with root privilege. If you are using Ubuntu/gnome, run the command below:

gksudo gedit /etc/udev/rules.d/80-programs.rules

Delete the line:

BUS=="usb", RUN+="/bin/usb-hotplug.sh"

.

2. Remove usb-hotplug.sh

sudo rm /bin/usb-hotplug.sh

.

3. Optional: remove beep

sudo apt-get remove beep

.

.