Command to tell what character encoding a file has

[Antony Stace <antony@example.com>]

Hi

A while back I used a command which would tell me the character encoding
of a file, ie in shift_jis or euc.  Now I cant remember the name of the
command.  Can someone please enlighten me on this commands name and also
where I can find c source for it.

Cheers

Tony