Function: recode-file-name

Change the encoding of FILE's name from CODING to NEW-CODING.
The value is a new name of FILE.
Signals a `file-already-exists' error if a file of the new name
already exists unless optional fourth argument OK-IF-ALREADY-EXISTS
is non-nil. A number as fourth arg means request confirmation if
the new name already exists. This is what happens in interactive use with M-x.