OT: assignment to errno RE: PATCH: ptyread eating CPU on Cygwin

["Andrej Borsenkow" <Andrej.Borsenkow@xxxxxxxxxxxxxx>]

> +	errno == EWOULDBLOCK

Not exactly relevant, but assignment to errno is a bad style. It may well be a
function (or some non-lvalue entity), espicially in case of threads support.
Also, I was really surprised recently to hear, that C9X and ISO C++ _require_
errno to be a macro.

There are probably many other places where errno is assigned to, of course.
But if we can avoid it - let's do it.

-andrej