offset, mp3....

Hello,

Someone posted:

"...The technique to do this is not complex as long as you have all the
tracks of the album as MP3 files. You calculate the length of the files and
create a TOC and calculate the discid just as you'd do with a CD..."


I have all mp3 from album, in corect order.
I need to calculate discId to get album info.

So my question(s):
1.  (...You calculate the length of the files ...) what length, sec, bytes,
bits,... ?
2.  (...and create a TOC ...) what is TOC and how to creati it ? :)
3. Discid calculation:
    ------------------
    Client command:
    -> discid ntrks off_1 off_2 ... off_n nsecs

    off_1 , off_2, what offset, in what , secs, bytes ?

That would be all...
...for now :)