Re: [RFC] patch's default backup behavior

On Fri, Apr 8, 2022 at 10:41 PM Warner Losh <imp@bsdimp.com> wrote:
>
>
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> On Fri, Apr 8, 2022, 9:26 PM Kyle Evans <kevans@freebsd.org> wrote:
>>
>> Hello!
>>
>> FreeBSD's patch follows historical patch(1) behavior w.r.t. backups,
>> where a backup is created for every file patched.
>>
>> I'd like to test the waters on switching this to the GNU behavior,
>> which feels a whole lot more reasonable. Notably, they'll only create
>> backup files if a mismatch was detected (presumably this means either
>> a hunk needed fuzz or a hunk outright failed). This yields far fewer
>> backup files in the ideal scenario (context entirely matches), while
>> still leaving backup files when it's sensible (base file changed and
>> we might want to regenerate the patch).
>>
>> Thoughts / comments / concerns? Cross-posted this to a couple of
>> different lists to try and hit the largest number of stakeholders in
>> patch(1) behavior.
>
>
> Could one select the old behavior? Or would it just be a change? A new -V value?
>

Yeah, the current behavior is actually represented by the `-b` flag.
With the new behavior, we'd specifically implement
`--backup-if-mismatch` (a nop from the beginning),
`--no-backup-if-mismatch` (turn off backups, equivalent to `-V none`
but "lighter" in that it won't override -b/-V) and we'd leave existing
flags otherwise alone.

> I like the Idea.
>
> Warner
>
>> Thanks,
>>
>> Kyle Evans
>>