bug#12365: Should cp -n return 0, when DEST exists?

[Eric Blake]

tag 12365 wontfix
thanks

On 09/06/2012 04:50 AM, Anoop Sharma wrote:
> When -n option of cp is used and the DEST file exists, then, as
> expected, cp is not able to copy the SOURCE to DEST.
> 
> However, cp returns 0 in this case.

cp -n is not mandated by POSIX, so we are free to do as we wish here.
But looking at history, we added -n for coreutils 7.1 in Feb 2009, and
the mail from that thread includes:
https://lists.gnu.org/archive/html/bug-coreutils/2008-12/msg00159.html

which states we are modeling after FreeBSD.  A quick check on my FreeBSD
8.2 VM shows:

$ echo one > bar
$ echo two > blah
$ cp -n blah bar
$ echo $?
0
$ cat bar
one

that FreeBSD also returns 0 in this case, and I don't want to break
interoperability.  Therefore, I'm going to close this as a WONTFIX,
unless you also get buy-in from the BSD folks.

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-- 
Eric Blake   address@hidden    +1-919-301-3266
Libvirt virtualization library http://libvirt.org

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