Usenet 1994 January/usenetsourcesnewsgroupsinfomagicjanuary1994.iso/sources/unix/volume25/classify/README

Text File | 1992-02-28 | 1.5 KB | 44 lines

    `classify' is a utility for comparing many files to each
other all at once.  For example, if you manage a collection
of diskless workstations, you can see which machines are
using the same rc.local file by executing the command

    classify /export/root/*/etc/rc.local

(or something like it ) on the server machine.

    If you want to edit the motd files on these
workstations, you can use a script like this:

    foreach i ( `classify -1 /export/root/*/etc/motd` )
        set ifamily=`classify -m $i /export/root/*/etc/motd`
        $EDITOR $i
        foreach j ($ifamily)
            cp $i $j
        end
    end

which groups the motd files into classes of identical files,
invokes the editor on one motd from each class, and then
propagates the changes to the other motds in each class.

    The `test?' files are sample inputs so you can see what
`classify' is doing.  Some of the `test' files differ only
in the case of some of their letters; some have extraneous
whitespace of various types, some are really the same as
each other ands some are genuinely different.

To-Do:

    `classify' might have better performance if it did
`stat' on files it was comparing to see what their i-numbers
were; if two files are on the same device and have the same
i-number, then they are necessarily identical, and don't
need to be compared character-by-character.  It might also
be worthwhile to keep a cache of the first block or so of
one file from each class, to save repeatedly opening and
closing files.

Mark-Jason Dominus
[e-mail]