Cygwin sparse file support: Please support fcntl(..., F_FREESP, ...)

[Corinna Vinschen]

On Feb  5 08:41, Cedric Blancher via Cygwin wrote:
> On Thu, 5 Jun 2025 at 09:07, Cedric Blancher <cedric.blancher@gmail.com> wrote:
> >
> > On Mon, 17 Feb 2025 at 11:07, Corinna Vinschen via Cygwin
> > <cygwin@cygwin.com> wrote:
> > >
> > > On Feb 16 16:27, Sebastian Feld via Cygwin wrote:
> > > > On Sat, Feb 15, 2025 at 4:15 PM Cedric Blancher via Cygwin
> > > > <cygwin@cygwin.com> wrote:
> > > > >
> > > > > Good afternoon!
> > > > >
> > > > > Could Cygwin 3.6 please support fcntl(...,F_FREESP,...) and
> > > > > cntl(...,F_FREESP64,...), as specified in
> > > > > https://docs.oracle.com/cd/E19253-01/816-5167/fcntl-2/index.html
> > > > >
> > > > > Lots of older software from Solaris, SUPER/UX, CrayOS use F_FREESP for
> > > >
> > > > QNX and AIX support F_ALLOCSP and F_FREESP
> > > >
> > > > > punching a hole into a file, and IMO it'll be nice if this works for
> > > > > Cygwin out of the box.
> > > >
> > > > +1
> > > >
> > > > Please also add F_ALLOCSP and F_ALLOCSP64 to allocate space in a file.
> > > > Like F_FREESP and F_FREESP64 it takes a struct flock/flock64, so it's
> > > > a pretty straightforward API.
> > >
> > > No, we won't do that. We're not adding any new feature to 3.6 this
> > > close to the release.
> >
> > What about now? Could this be implemented for Cygwin 3.7, please?
> 
> Hello?

These are equivalent to the fallocate stuff.  Just add an #ifdef to
the source.  You'll have to do that on Linux anyway.

If you want this in Cygwin, please consider https://cygwin.com/acronyms/#PTC


Corinna