Re: [PATCH] Cygwin: redefine some macros for Linux compatibility

[Corinna Vinschen <corinna-cygwin@cygwin.com>]

On Jul  6 16:51, Ken Brown wrote:
> On 7/6/2022 4:25 PM, Ken Brown wrote:
> > Patch attached.
> > 
> > I wasn't sure whether the API bump was warranted for such a trivial
> > change.  But the fact is that some programs compiled prior to the patch
> > will behave differently if they are recompiled after the patch.  For
> > example, emacs limits the number of open subprocesses to FD_SETSIZE, so
> > this number will change when emacs is recompiled for Cygwin 3.4.0.  Is
> > that a good enough reason to bump the API?
> 
> Oh, wait a minute there's already been an API bump from 341 to 342, so I
> guess there's no need for another.  I could just add the FD_SETSIZE and
> NOFILE changes to the explanation for that bump.

Just bump.  It doesn't hurt.

The patch is fine.  I was going to say we should drop OPEN_MAX, too,
just as on Linux, but that would be wrong because we really use OPEN_MAX
as a limit.


Thanks,
Corinna


Idle musing:

We could think about dropping OPEN_MAX, too.  getdtablesize() and
sysconf(_SC_OPEN_MAX) could be implemented as requesting the rlimit_cur
value of getrlimit(RLIMIT_NOFILE), as in glibc.  Per the current Linux
source, the start values for RLIMIT_NOFILE are 1024 as soft, and 4096 as
hard limit...