Path: utzoo!attcan!uunet!lll-winken!ncis.llnl.gov!helios.ee.lbl.gov!pasteur!agate!bionet!csd4.milw.wisc.edu!mailrus!tut.cis.ohio-state.edu!osu-cis!mstar!karl
From: karl@mstar.UUCP (Karl Fox)
Newsgroups: comp.sources.bugs
Subject: Re: bug in public domain diff?
Message-ID: <985@mstar.UUCP>
Date: 23 Jan 89 20:01:05 GMT
References: <8901191545.AA18697@explorer.dgp.toronto.edu>
Reply-To: karl@mstar.UUCP (Karl Fox)
Organization: Morning Star Technologies, Columbus, Ohio
Lines: 24

Well, I *too* have also written a pd diff that *also* gives the same
output as the 'real' diff on these two files.  It uses a different (and
much faster) algorithm, one described by Webb Miller and Gene Myers in
"A File Comparison Program", _Software - Practice and Experience_,
November 1985 (with permission of the author, even).  This is the same
basic algorithm used by GNU diff, except that mine doesn't have the
fancy all-different-line-removal stuff that GNU diff does (which speeds
it up a lot on very different files), nor does it have the stuff that
massages the results to "look better" but make it also different from
regular diff.

Mine supports the -e, -f, -b, -h, -s, -r, -l, -S, -D and -c options,
which I think is the same as BSD diff.  I wrote it because the old diff
was eating up our machine when we used SCCS on very large files.  It
used to be, "type delta and go to lunch"; now it never takes more than
several seconds.

Maybe we should assign a central Diff Naming Authority to hand out
names like ndiff, gdiff, diff1, diff2, or maybe we should all post at
once.  Let the customer choose, just like "Sun Memory at Bargain Prices".
-- 
Karl Fox, Morning Star Technologies
UUCP:     osu-cis!mstar!karl -or- pyramid!mstar!karl -or- sequent!mstar!karl
Internet: osu-cis!mstar!karl@tut.cis.ohio-state.edu