How to create a folder which will change its contents’ ownership to what the folder has?

Question

In a GNU/Linux OS there is no way to change ownership of a file until you are root. But what if I want to hide my system’s username e.g. before sending a file to someone, because some things like tar will try to keep it?

What I think about is something like

# mkdir --mode=????? /tmp/nobodysfiles
# chown nobody:nobody /tmp/nobodysfiles

$ whoami
popcorneater
$ ls -l ~/file
-rw-r--r-- 1  popcorneater popcorneater 12345 oct.  18 11:10
$ cp ~/file /tmp/nobodysfiles/
$ ls -l /tmp/nobodysfiles/file
-rw-r--r-- 1 nobody nobody 12345 oct.  18 11:11

Answer 1

Prepare your archive inside a fakeroot session. Fakeroot was designed precisely to prepare a directory structure's ownership and permissions before building an archive.

fakeroot bash
chown -R root:root nobodysfiles
tar czf nobodysfiles.tgz nobodysfiles