Where does the `rename` command come from?

Question

Where does the rename command come from?

user@host> dpkg -S /usr/bin/rename
dpkg-query: no path found matching pattern /usr/bin/rename

Answer 1

Surprisingly, it comes from the rename package.

pilot6@Pilot6:~$ ls -l /usr/bin/rename
lrwxrwxrwx 1 root root 24 окт 17  2013 /usr/bin/rename -> /etc/alternatives/rename
pilot6@Pilot6:~$ ls -l /etc/alternatives/rename
lrwxrwxrwx 1 root root 20 апр 29  2016 /etc/alternatives/rename -> /usr/bin/file-rename
pilot6@Pilot6:~$ dpkg -S /usr/bin/file-rename
rename: /usr/bin/file-rename

Answer 2

You will probably find that it's a symbolic link that is managed by the update-alternatives mechanism:

$ ls -l $(which rename)
lrwxrwxrwx 1 root root 24 Jun 29  2016 /usr/bin/rename -> /etc/alternatives/rename

You can see the optional implementations using

$ update-alternatives --list rename
/usr/bin/file-rename
/usr/bin/prename

and can choose between implementations using

update-alternatives --config rename

FWIW file-rename is provided by the rename package, whereas the original prename is provided by perl itself. From apt-cache show rename:

This package provides both a perl interface for renaming files (File::Rename) and a command line tool 'rename' which is intended to replace the version currently supplied by the perl package.

As if this was not already confusing enough, you may also come across yet another rename from the util-linux package - see What's with all the renames?

Answer 3

If we're talking about /usr/bin/rename, which is a pretty nifty perl script, then rename command belongs to its own separate package.

rename:
  Installed: 0.20-4
  Candidate: 0.20-4
  Version table:
 *** 0.20-4 500
        500 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        500 http://archive.ubuntu.com/ubuntu xenial/main i386 Packages
        100 /var/lib/dpkg/status

In case of Korn shell and its derivatives, rename is a shell built-in command.

$ echo $SHELL
/bin/mksh

$ type rename
rename is a shell builtin