Re: [PATCH 01/10] strbuf: Add strbuf_read_noblock

[Jeff King <peff@peff.net>]

On Thu, Sep 17, 2015 at 10:45:40AM -0700, Stefan Beller wrote:

> > You _can_ loop on read until you hit EAGAIN, but I think in general you
> > shouldn't; if you get a lot of input on this fd, you'll starve all of
> > the other descriptors you're polling.  You're better off to read a
> > finite amount from each descriptor, and then check again who is ready to
> > read.
> 
> That's what I do with the current implementation. Except it's not as clear and
> concise as I patched it into the strbuf_read.

Is it? I thought the implementation you posted bumped the existing
strbuf_read to strbuf_buf_internal, including the loop. So as long as we
are not getting EAGAIN, it will keep reading forever. Actually not quite
true, as any read shorter than 8192 bytes will cause us to jump out of
the loop, too, but if we assume that the caller is feeding us data
faster than we can read it, we'll never exit strbuf_read_nonblock() and
serve any of the other descriptors.

-Peff