On Sun, 5 Jan 2025 at 17:31, Brian Inglis via Cygwin <cygwin@cygwin.com> wrote: > > On 2025-01-05 06:52, Takeshi Nishimura via Cygwin wrote: > > On Sun, Jan 5, 2025 at 1:06 PM Václav Haisman via Cygwin wrote: > >> On 05. 01. 25 7:31, Cedric Blancher via Cygwin wrote: > >>> Could Cygwin implement copy_file_range() support, including sparse > >>> file support so holes are preserved, and > >>> FSCTL_DUPLICATE_EXTENTS_TO_FILE support? > >> > >> In theory, this could be used to implement that function. In practice, > >> the block cloning is only supported by ReFS. See > >> <https://learn.microsoft.com/en-us/windows/win32/api/winioctl/ni-winioctl-fsctl_duplicate_extents_to_file> > > > > All Windows Server (2019, 2022) installations we have. and those which > > I know about, use ReFS (except in cases where Alternate Streams are > > required). > > AFAIK SMB3 also support FSCTL_DUPLICATE_EXTENTS_TO_FILE, so this would > > be a HUGE win for Cygwin > > Cygwin has supported sparse files since 2000, mount option to enable it for > over > a decade, inode sparse ioctl flag for half that, and automatic support on SSDs > just over a year ago: > > https://cygwin.com/git/?p=newlib-cygwin.git&a=search&st=commit&s=sparse&h=363357 > > https://cygwin.com/git/?p=newlib-cygwin.git;a=commitdiff;h=05297c > > https://cygwin.com/git/?p=newlib-cygwin.git;a=blob_plain;f=winsup/cygwin/include/cygwin/fs.h > > It works on NTFS, include remote mounts, but I don't know about other > filesystems?
I know about sparse file support in Cygwin. My request was for sparse file support in copy_file_range() when Cygwin implements this function Ced -- Cedric Blancher <cedric.blanc...@gmail.com> [https://plus.google.com/u/0/+CedricBlancher/] Institute Pasteur -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
