cdif: word context diff

Copyright (c) 1992-1998 Kazumasa Utashiro <utashiro@iij.ad.jp>
Internet Initiative Japan Inc.
3-13 Kanda Nishiki-cho, Chiyoda-ku, Tokyo 101-0054, Japan

$rcsid = q#Id: cdif,v 1.15 1999/02/03 13:14:20 utashiro Exp #;
Original: 1992/03/11

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