Re: PATCH: Support Windows in event-loop.c

["Eli Zaretskii" <eliz@gnu.org>]

> Date: Thu, 21 Apr 2005 14:15:28 -0700
> From: Mark Mitchell <mark@codesourcery.com>
> CC: Eli Zaretskii <eliz@gnu.org>,  gdb-patches@sources.redhat.com
> 
> Daniel Jacobowitz wrote:
> 
> > Anyway, if Mark can come up with a select wrapper, then maybe we can
> > drop the question entirely.
> 
> I'm sure I can, if that's the only way to get this functionality into 
> GDB.

It's not the _only_ way, but it's the _preferred_ way, at least in my
opinion.  (If other maintaners, besides Daniel, disagree with me,
please speak up.)  If it becomse clear that doing what I asked is
going to be a major project, I assure you I will withdraw my
objections right there and then.

> But, the emacs select wrapper is hardly a full implementation of 
> select; for example, it only handles file descriptors waiting for 
> "read", not "write".

AFAIK, GDB also needs to watch handles only for readable events, not
for writable events.  You will see that does not add the GDB_WRITABLE
bit to the mask it passes to select/poll.  If we wish to guard against
possible changes in the future that will break the emulation, we could
add some code that will yell bloody murder if select is ever called to
watch handles for writability.