Support for other events

[notfound4]

Support for checking for user defined events at the same time as checking for i3 events (like input in a fifo file, data on cin, etc...). If one of those events is catch, a callback function (given by the user) is called.

Useful if you want to use this library to create a panel.

[drmgc]

Please, atomize your commit; It's too complex. And describe more about "user defined events". If I've understood them right, they are not in the jurisdiction of i3ipc++.

[notfound4]

Well, the problem I faced was :

• I am trying to wrote a custom panel for i3. It needs to read event from libxcb, a fifo file, and i3 (using your library). It would be wasteful to create a thread for each of them.
• So, I modified your code to be able to wait for multiple event in the same time in the same thread (using poll).
• However, you are right this is not in the jurisdiction of i3ipc++. A better way to achieve this objective would be to just add a method that allow users to access the file descriptor associated to i3.

So, I'll revert my changes and add this method. Sorry for the time loss.