Well, I'm no professional yet but I'm finding it pretty good coding in C while using the proper lintian together with clang, I also use the package script, which allows me to run the code from within the editor. If you give enough tweak, I believe it can be a pretty usefull IDE. Didn't try any gdb integration yet.

The languages Atom supports have very little to do with the languages Atom is built with. Anyone can add first-class language support to Atom and many have.

I watch all the new Atom packages as they are released, which is taking more and more of my time, and I have been shocked at how many languages there are. There are many many weird languages I've never heard of.

Its fine. I'm using it for: Go, Perl, NodeJS, Scheme, Bash, C++, and Rust.

You might have to add some of the syntax highlighting etc, but there are packages for most languages available directly in the built in package manager.

C? It has syntax highlighting, but it's very obviously geared towards web development.