Re: BTRFS file clone support for cp

[Tomasz Chmielewski]

Jim Meyering wrote:

> With classic cp, if I copy a 1GB non-sparse file and there's less
> space than that available, cp fails with ENOSPC.
> With this new feature, it succeeds even if there are
> just a few blocks available.

Is it good or bad?


> Also, consider (buggy!) code that then depends on being able to modify
> that file in-place, and that "knows" it doesn't need to check for ENOSPC.
> Sure, they should always check for write failure, but still.  It is
> a change.

On a multiuser system, that (buggy) tool would fail anyway if something 
else adds enough new data to the filesystem in the meantime.

But sure, it's a change.


--
Tomasz Chmielewski
http://wpkg.org