I am currently studying X11 and trying to implement some applications using the XCB library. I was wondering if questions related to XCB are on topic here. While the problems that I usually face are problems in my code, I think they may be caused by a bad understanding of X11 itself. So, are XCB related question allowed here?
Great question; thank you for asking on the Meta site first!
Starting from the starting point, our Help Center says, in What topics can I ask about here?:
UNIX C API and System Interfaces ( within reason )
Initial opinion in Unix C API calls ontopic?:
I think questions about the system interfaces (i.e. the C API) should be on-topic here, as long as they're about common unix interfaces (not necessarily POSIX, but excluding very different systems like Cocoa) and essentially language-agnostic. ...
Note that this answer only applies to questions about issues like signal delivery, terminal modes, sockets, … which are exposed in similar ways in most languages. It can apply to other low-level APIs associated with unix, e.g. X library calls (that map closely to the X11 protocol) or D-Bus communication.
... with a heuristic at the end:
will the question interest only programmers, or also users and administrators?
A sysadmin debugging why a server won't start with truss/strace output is on-topic here.
A programmer debugging why his kernel module is causing an OOPS is off-topic.
Note that the above answer is from 2010; there are follow-up threads:
If your question is about writing code using Unix or Linux libraries, it should go to Stack Overflow (provided it follows that site's guidelines too). Questions about how common APIs work (say POSIX interfaces) can be on topic on U&L though.
there seems to be general agreement that programming questions are, with some exceptions, off topic here
- Topics for users and administrators: ask here.
- Topics for programmers: ask on Stack Overflow.
When I looked up XCB in Wikipedia, I got:
X protocol C-language Binding) is a library implementing the client-side of the X11 display server protocol. XCB is written in the C programming language ...
In my opinion (and I suppose by proxy anyone that votes this up), questions about XCB would more interest programmers and not System Administrators or users. It's one layer below any common interaction with X11. I'd say that
problems in my code are off-topic while an understanding of
X11 would be on-topic.
Just remember that people on SO prefer to talk code, not concepts, so questions are much better received there when you have a sample of code demonstrating the problem you're asking about.