My bad old-time-y-ness

I wanted to post something relatively quick tonight, so here’s a bit of poking I’ve been doing. I’ve yet to get anything interesting with bluetooth between my laptop and my iPhone. That and I’m a pretty paranoid person so I keep the bluetooth turned off. However, I decided to leverage my paranoia to give me a reason to keep bluetooth on.

So I did some poking around and came up with the shell script below… yes, I know shell scripts are old-time-y, and I’m even more aware that my bash skills have slipped with age.

I’m working on some python code but rather then looking crufty and forgetful that will come off as clueless and juvenile so we’re sticking with shell for now, because it works (which is all most shell scripts can claim anyway).

A few things that made this hard has been the evolution of dbus and the apps built on them. There’s some interesting articles out there but most tell you how to implement a dbus service and not how to make calls to an existing one, i.e. how in the world can I query dbus methods rather then just “sniffing” them out.

The example in this post incorrectly lists the locking target as "org.gnome.ScreenSaver.setActive" when it is actually "org.gnome.ScreenSaver.Lock" also it is listed in the method list. The command dbus-monitor will help immensely, and if someone can tell me why ^C doesn’t work and I end up having to ^Z and then kill %1 that would be great.

Also the Poke method doesn’t initiate activity in such as way as to produce an “unlock” screen as you’d expect.

Another example of frustration is this python sample from RedHat which fails, i.e. the object returned by dbus.SystemBus() has no member get_service().

I grew using KDE and although I run GNOME now I miss many KDE things, but I’m hopeful that dbus becomes a common communication system for all things on Linux, although there are times when it feels like reinventing the wheel like why can’t network manager just use the standard ifconfig and iwconfig commands.

However, I think I’ll save trying to figure that part out until after I get my python in shape.

My apologies for the code formatting, I’m not sure how to do this cleanly in WP, however, I hope this helps someone out there!


### You’ll need to change the 00:FF:FF:FF:FF:FF below to the bdaddr of your phone


while true; do

TEST=`/usr/bin/sudo /usr/bin/l2ping -s 1 -c1 -t 1 00:FF:FF:FF:FF:FF 2>/dev/null`
echo $TEST | grep “1 sent, 1 received” &> /dev/null && jay_found=1

if [ $jay_found -eq “1” ]; then
echo “I found your phone”;
sleep 10
dbus-send –session –type=method_call –dest=org.gnome.ScreenSaver /org/gnome/ScreenSaver org.gnome.ScreenSaver.Poke boolean:true
if [ $lock_it -eq “0” ]; then
echo “Not yet!”;
sleep 30
elif [ $lock_it -eq “1” ]; then
echo “I think I should lock your screen”;
# dbus-send –session –type=method_call –dest=org.gnome.ScreenSaver /org/gnome/ScreenSaver org.gnome.ScreenSaver.Lock boolean:true
# I don’t know that there’s a good alternative here
sleep 60

About jay

I'm trying to build something interactive where I can learn from others and hopefully share useful knowledge too.
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2 Responses to My bad old-time-y-ness

  1. jay says:

    Hey Kyle,
    Thanks for the quick post. Yea that API doc is the same link. Thinking about it further I took “Activitate the Screen Saver” meaning “turn it on” but “turn it on” is probably not the same thing as “run it”. i.e. “turn it on” just means it will lock the screen when the inactivity timer kicks in.

    My 2nd problem is that “Poke” is supposed to simulate activity, which I suppose means “keep it from running” but when it’s already “running” i.e. locked, it doesn’t cause the screen saver to show the “enter your password” box.

    I’ll have to keep messing w/ it.

  2. Kyle says:

    On my way to a meeting, so I didn’t verify this, but I posted about the screensaver DBus API back in June and my post included a link to the API docs. Does it match the email to the mailing list?

Comments are closed.