Undocumented weird thing with hard links and rename(2)

published: 04 Jul 2004 | tags:

Try this:

myers@soap:~/tmp$ touch a
myers@soap:~/tmp$ link a b
myers@soap:~/tmp$ mv a b
myers@soap:~/tmp$ ls
a  b

What? Why is “a” still around? Turns out rename(2) will not delete the first file in a rename if the second is linked to the same inode. AND the man page doesn’t say anything.