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Today, I needed to find out why an X client did not receive any input events. Or to put it differently: to find out which process the X server was sending events to.

Running an strace on the X server process reveils the socket the X server writes X events to. Assuming that the file descriptor of this socket is 38, the following provides a way to find out which client will receive the events:

ls -la /proc/`pidof Xorg`/fd/38

This will print something like:

lrwx------ 1 root root 64 Nov 22 04:13 /proc/306/fd/38 -> socket:[4036]

So the UNIX socket is 4036. This is only the X server side of it. The following shell command will yield the complete socket pair:

grep 4036 /proc/net/unix -A1

The output of this is:

eff24600: 00000003 00000000 00000000 0001 03  4036 @/tmp/.X11-unix/X0
eff24000: 00000003 00000000 00000000 0001 03  5048

I think /proc/net/unix has all UNIX socket connection pairs in adjacent lines, so in this case the line below 4036 holds the client socket, which is 5048. Note that you may have to use -B1 instead of -A1 as the order of sockets may be different. Searching for the process that uses 5048, you can do this:

ls -l /proc/*/fd/* 2>&1 /dev/null | grep 5048

The output in this case could be something like this:

lrwx------ 1 root root   64 Nov 22 04:12 /proc/663/fd/36 -> socket:[5048]

This means that the X events are sent to the client with PID 663 with the corresponding file descriptor being 36. This can then be used in an strace on PID 663 to find out more about the reception of events etc.

Fun.

Whatever MeeGo was, it never made it into the open source mainstream, which I consider to consist of projects actively worked on by volunteers and companies alike, and didn’t manage to become an project attractive enough for individual open source enthusiasts not driven by money to make substantial contributions.

There is enough room to speculate over the reasons why this is. My personal take is that MeeGo failed to be a successful open source project because the corporate commitment to the open source idea was not strong enough and expectations were too high right from the start. 

Open source projects start with an idea and evolve into a proper product over time. Sometimes they are developed incrementally, sometimes it happens that big parts of them are replaced all at once. The idea behind an open source project may be huge but they all start off with baby steps. MeeGo, however, wasn’t supposed to. The idea behind MeeGo was big, and due to market pressure it was expected to become complete and successful quickly. It occurs to me that the idea was to sort of guarantee success by providing the project with professional, corporate governance. 

I think everyone who started working on open source as a hobby knows that this is something a lot of hackers are not comfortable with. An open source project under corporate leadership may easily suffer from top-down decisions that give developers the feeling of working in a restrictive environment rather than a playful one. I’m not surprised by the fact that the only people I know ever contributed to MeeGo worked either for/with Intel or Nokia.

It isn’t the technologies, tools or frameworks that are reason for the failure of MeeGo. KDE and GNOME are large and successful projects based on Qt, GTK+, Clutter, D-Bus-based desktop middleware etc. What has lead to failure in my eyes—the eyes of an outsider, open source developer and potential user—is that the dynamic nature of open source projects conflicted with corporate expectations and hopes for a quick success they needed so badly. Add to that the pressure on Nokia, the corporate culture clash of two global information technology companies and the fast pacing world of mobile devices and interfaces, and you have a pretty explosive mixture.

Personally, I won’t place my bets on Tizen. I can only imagine how frustrated and disappointed everyone who tried to get involved may be today, even those who contributed to MeeGo as part of their work for Intel, Nokia or one of the many smaller companies that make up the corporate part of the open source ecosystem. It is also frustrating for me as a developer aiming for a job in open source and desktop/mobile/UI technologies.

I guess the mobile open source platform we are all hoping for will be there some day. But it will only appear slowly, driven by the efforts of enthusiastic individuals with big ideas, realistic expectations and sound knowledge of the pace and dynamics with which open source projects grow and mature. This of course relies on open hardware and I don’t know enough about the manufacturing industry to predict the availability of open, hackable devices in the near future.

In the meantime, the best we can do as open source software developers is improve the base OS and innovate in desktop/mobile/UI technologies by experimenting with new ideas and extending existing frameworks. I’ll help where I can.