1.5.20(0.156/4/2) pipe hangs, dos files

[Lev Bishop]

On 8/2/06, Darryl Mile:
> Okay you seem to have some understanding as to how and why it failed for
> the "unison" group of users.  Do you think the commented out code is
> fixable in any so that all cases work correctly ?

Iff you can come up with a way to distinguish the two situations: 1)
blocking read is in progress. 2) no blocking read is in progress. I
can't come up with a way of doing that which is reliable in all cases
of multiple readers on the same pipe, multiple writers on the same
pipe, non-cygwin windows native processes involved, etc. Worse, I
can't even come up with a way that helps the more common cases (single
reader, single writer, both cygwin processes) and falls  back to the
current behaviour for the other cases. Instead, everything I've tried
would deadlock in those less common cases.

There probably is a way to do it, but enough people have spent enough
time pondering this at this point, that you can be assured it isn't
something immediately obvious.

Anyway, at this point, if you can code something up and show that it
works, then that's more likely to impress the maintainers than further
talking. (And even if the maintainers don't accept the patch, if it
fixes the problem for you, then there's nothing stopping you from
using your own patch for your own purposes, and even distributing it
to anyone else who finds it useful. That's the nice thing about the
GPL).

Lev

--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/