Well, it's not quite correct since for example httplib.py tries to handle EINTR. The fundamental problem with socket.readline() is that it does internal buffering so that getting EINTR results in data being lost.

I don't think it has to be fixed in C, since recv() is very low-level interface and it is expected to return EINTR on signal, so that "fixing" it there could possibly break software that relies on this behaviour. And I don't quite buy your reasoning - "since it's broken in few more places let's keep it consistently broken everywhere". To me it sounds like attempt to hide the head in the sand instead of facing the problem at hand. Fixing socket.readline() may be the first step in improvind the library to handle this condition properly.