From: torvalds@klaava.Helsinki.FI (Linus Torvalds) Subject: Re: minix fs with 30 chars filenames Date: 3 Aug 1993 20:42:22 +0300
I already replied to Laszlo by email, but as he may not be the only one
who doesn't know about this, it might be a good idea to post publically.
In article <23m5r9$a6o@ionews.io.org> las@io.org (Laszlo Herczeg) writes:
> Do I just change the minix_fs.h to get the 30 character filenames
>in the Minix file system?
>
> I heard that the Minix fs code supports both 14 and 30 character
>filenames, so maybe I just have to change the define from 14 to 30 chars?
The minix fs code does indeed support both 14-char (original minix) and
30-char filenames: it doesn't even need recompilation, but does the
check automatically at mount-time on a fs-by-fs basis. In fact, the
actual filesystem routines are written generally enough so that they can
handle other lengths as well (of the length '(2^n-2)' - 14,30,62,126 and
254), but the place where the current mount-routines only know of two
different magic numbers which correspond with either the 14- or 30-char
filesystems.
However, to get a 30-char minix filesystem you do need to re-mkfs it
with the "-n30" parameter - this assumes that you can find a mkfs binary
that supports it (all the never versions should, assuming that my
changes got to the people keeping these things up). As mkfs will
destroy any data on that partition, moving from 14 to 30 char names
usually involves a full backup, and is not any easier than changing
filesystems altogether (and ext2 and xiafs naturally allow even longer
filenames along with bigger partitions).
Linus