[Mono-devel-list] why .custom files in mono tarballs?

[Anset]

Hi,

I've decided to delve into the mono class library source code to figure out
why my code breaks.

In the tarball, I find some .cs files, and a lot of .custom files, that
appear to contain regular c# code.

Can anyone tell me why these .custom files are used and how they are
different?

If anyone could point me to a web page with this kind of info I would
greatly appreciate it.

Thank you very much.

Anset