Automatically changing the absolute scale

[Skippy]

Hi folks,

Thanks for this program, blahblah, let's shorten it : if I use it, chances are
that I like it. ;-)

Here is my question : is there an easy way to change the tonality of a lilypond
file ?

I mean, say that I want to write some music I have in mind. Unfortunately, it is
not in an obvious tonality, say for instance F# major, so transcripting it will
be a pain : so I write it in C major, using "c" for "fis" and so on. However,
once I am done, I would like to add 3 tones to each note, to output F# major
(without having to do it note by note obviously…). Is there a way to do this ?
Something like "\addtones 3" ?

Thanks.