The FOSS.in experience

As some of you know (possibly because I have been raving about it so much) this year's FOSS.in was held at Bangalore from 1st to 5th of December. I attended the conference on 2nd and 3rd of December. My plan was to attend all the 5 days, but some inevitabilities at work made it impossible.

The trip started on a very good note as I boarded the Kingfisher flight from Lohagaon on 2nd of December. For the entire duration of the flight, I was kept entertained by the very nice show on the smallish personal TV : Kingfisher calendar girls. The flight was half an hour late which messed up my already tight schedule. I took a shuttle to Jayanagar from the airport (which takes approximately one and a half hour), went to the hotel room and was out within 90 seconds and reached Nimhans Convention Centre just in time to catch Rahul Sundaram's talk on the Fedora buildsystem. Before lunch, I also managed to catch some bits of the talk by James Morris on seLinux sandboxing. Kedar had a fun time mocking my formal attire. (In my defence, I didn't know people come casually to the conference. I thought everyone will be in tip-top formals)

After a surprisingly great lunch, I went to attend Kedar's talk on Fedora-ARM (the reason I was at the conference). The attendees included many Fedora guys, some interested students and some others that I cannot place. Kedar talked on the status of Fedora-ARM, how to contribute, ARM or secondary arch specific issues and other stuff. Read here for more info. Rahul inaugurated the dist-f13 tag with his gnote build. After that was Rahul's talk on how to create a customized Fedora remix. I was looking forward to this particular talk since the idea of making a remix for sheevaplug has been playing into my mind since a while now. It was insightful. I moved on to attend Holger Frether's "How to make WebKit faster". It wasn't what I was expecting, but Holger gave a nice demonstration of how to use a number of well-known and less-known tools to measure performance. His focus was on beagle-board. The best talk of the day was the Keynote by Harald Welte. He talked about bringing open-source to less explored platforms like GSM, RFID, etc. Very Very inspiring!

As the day wrapped up, we decided to head to the Forum Mall for some sight-seeing (ahem). After some window-shopping, trying out fresh baked cookies (which turned out to be horrible) and exploring the Landmark bookstore, we went to have a brilliant lunch at the Anand Adiyaar Bhavan. Later we stopped by at the Corner House for desserts. I dared to order  "Death by Chocolate" not thinking once why it was named so and ignoring Kedar's warnings. The result was disastrous. I never thought chocolate would ever nauseate me so much! A tip for the readers: if you ever order that at Corner House, share one between 5 people.

Attended Lennart Pottering's "Pulseaudio Internals" on the second day. He focused on the do's and dont's on System programming. Very insightful! He is a very good speaker. I wanted to talk to him (like REALLY wanted to talk to him), but a couple of guys just wouldn't let him go! They crushed my dream :-(.  After another fabulous lunch, attended Rahul's talk on PackageKit and Harald Welte's workout on GSM. Went to the Nokia Maemo's booth and got a peek into how they are using Linux on their ARM core. Maemo is one neat piece of hardware. I would certainly recommend it to anyone looking for an open-source phone.

I really wanted to attend the Keynote by Milosch Mariac, since rumour had it that they are using Fedora-ARM in their product. Kedar later confirmed that the rumour was indeed true. But, sadly I had to fly back to Pune :-(.

Some of the things that really impressed me were:

• Lots and lots of students attending the conference. They get a nice exposure through all the workouts and talks. 
• Wireless connectivity on the entire campus. Really made me realise how important my laptop is! I looked up so many terms that I heard/overheard. Very educational.
• There was nothing formal about it and people were so passionate about technology.
• Very Very educational.

It was my very first conference, so I wasn't as proactive as I should have been, but I was better at it on the 2nd day than the first. I look forward to FOSS.in 2010 :-).

PS: Kedar called me later just to tell me that he talked to Lennart and Milosch. grrrr. Jealous!

I want to shout this out a thousand times!

A recent discussion on a fedora mailing list:

> I'd suggest that anyone who sets up a system without any user accounts
> _and_ somehow needs a GUI to configure the system _and_ can't manage
> to figure out the settings to change so they can login as root should
> probably not be pretending to be a competent administrator.
>
> Are there not enough examples from Windows of why it's a terrible idea
> to run with full administrator privileges -- especially software like
> web browsers?
>
>   
Look guys, I didn't ask for a Lecture on how to do things your way, I
just ask where is Konqueror in Root.

How very true! Many a times, I know what risk I run by using GUI as root user, but I still want to. I have my calculations of risk. They have no right to disable running stuff as root. Make it hard. Okay. Spew out warnings. I don't care. But, just let the thing work! Disabling it is just imposing your viewpoints on everyone and it is NOT alright!

Lots of Love,
Me

Atomic operations from userspace

Lennart Pottering, the pulseaudio developer, has made some interesting observations on emulating atomic operations, using ARMv5 as a running example. Obviously, the post is about architectures who do NOT have hardware support and lack or have minimal kernel support. (However, some Andrew Hayley has noted an obscure kernel API for the purpose). A good read overall.

I don't fully understand the post yet, but I intend to dig deep into this once I get free time.

FYI

yum spookiness

Recently, I started getting tracebacks on a simple "yum update"

# yum update -y
Loaded plugins: fastestmirror, presto, refresh-packagekit
Setting up Update Process
Traceback (most recent call last):
  File "/usr/bin/yum", line 29, in <module>
    yummain.user_main(sys.argv[1:], exit_code=True)
  File "/usr/share/yum-cli/yummain.py", line 309, in user_main
    errcode = main(args)
  File "/usr/share/yum-cli/yummain.py", line 178, in main
    result, resultmsgs = base.doCommands()
  File "/usr/share/yum-cli/cli.py", line 352, in doCommands
    return self.yum_cli_commands[self.basecmd].doCommand(self, self.basecmd, self.extcmds)
  File "/usr/share/yum-cli/yumcommands.py", line 368, in doCommand
    return base.erasePkgs(extcmds)
  File "/usr/share/yum-cli/cli.py", line 641, in erasePkgs
    if not self.remove(pattern=arg):
  File "/usr/lib/python2.6/site-packages/yum/__init__.py", line 3023, in remove
    (e,m,u) = self.rpmdb.matchPackageNames([kwargs['pattern']])
  File "/usr/lib/python2.6/site-packages/yum/packageSack.py", line 224, in matchPackageNames
    exactmatch.append(self.searchPkgTuple(pkgtup)[0])
IndexError: list index out of range


Initially I thought it was due to corrupted yum metadata. So, I ran a "yum clean all" to no avail. But then, rpm also started acting spooky. "rpm -q kdelibs" returned nothing although I was pretty sure I had installed kdelibs (since amarok depends on it). Looked like a bombed rpm database.
So, the simple solution was to run "rpm --rebuilddb" which reconstructs the rpm database. Everything worked like a charm after this!

PS: This is more a note to myself than a post. If it helps anyone, well and good. :)

Using the IRC

(Following are some ways I know to ensure privacy and avoid someone spoofing your identity.)

First, I'll recommend registering yourself with a nickname so that no one can steal your identity.
Use this nice tutorial to register your nick on freenode. Other services will have their how-tos.

Second you might want to disable FINGER, TIME and VERSION requests.
FINGER enables getting personal information like Email. TIME gives out your location information and VERSION gives out the OS and client names and versions you are using. Knowing the versions, an attacker might try a specific exploit.
Here is a nice tutorial to do it in xchat. Look at the client specific documentation if you use a different client.

Also, you might want to hide yourself from the global who/whois list (The way to do it on freenode is:)
/umode +i
(+i = invisible mode)

Leave a comment if you know a good addition to this list.

Automake supports cscope and ctags!

Finally!
Automake includes support for automatic generation of cscope and ctags targets. Now, theoretically, you can take any open-source project which uses GNU build system (and manyyy of them do) and type "make cscopelist" or "make ctags" or "make tags" and it will automatically generate the tags! Not that generating tags was a very difficult process earlier, but with support in automake, we can tinker around with the tags a lot.

Eg. If there is an arch/ subdirectory in your source-code and you don't want your cscope tags to be polluted by the IA64 code that you don't really care about, you can do it very easily by modifying the Makefile.am file in the arch directory.

I.e. you can easily control how your tags are generated!

This is the commit that went in,
http://git.savannah.gnu.org/cgit/automake.git/commit/?id=ffad481680a4e6a8f220c70f07b105c9f3f2dfdf


Hail automake!

Masochism ...

Objective : Whenever volumes are mounted, I see volume icons on my Desktop. I want to hide the icons because they mess with my wallpaper.

Method 1 : Find a GUI option.
Result : None present

So, after half an hour of grep-ing in ~ and lsof-ing, I found out that the option I need to set is probably hidden deep down into one of the huge gconf schemas.

 So, I started to learn the gconftool-2 tool. Its one nasty command.

# gconftool-2 --dump / > /tmp/gconf-dump
# wc -l /tmp/gconf-dump
96086 /tmp/gconf-dump


Crap! that huge!
So, I grep-ed for various keywords for another 15 min. Thats when I got a match.


# grep volumes /tmp/gconf-dump
<key>/schemas/apps/nautilus/desktop/volumes_visible</key>
(hiding other results for the purpose of sanity)


So, thats the key I have to flip. Pored over the man-page of gconftool-2 and here is the magic command:


# gconftool-2 --type bool --set /schemas/apps/nautilus/desktop/volumes_visible false


Similarly, you can also turn-off, trash_icon_visible, network_icon_visible (hides samba mounts), home_icon_visible and computer_icon_visible. and voila! A clean desktop!

You'll have to logout and login back again to see the changes. Although, I am sure there's better way. (Like to ask gconfd to reload the config). But, its 2:00am already and I need some sleep. So, I'll update this post tomorrow!

Whew!