[ahl]

Fair enough; and right now cp doesn't use the fast clone functionality, but it assuredly will. I'm not sure 'cat <file >file.dup' is reasonable for most users.

[ghshephard]

Just teach everyone to use dd instead - dd if=file of=file.dup :-)

[TazeTSchnitzel]

If they patched it to use a different syscall, maybe.