Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!bloom-beacon!mit-eddie!uw-beaver!teknowledge-vaxc!mkhaw
From: mkhaw@teknowledge-vaxc.ARPA (Mike Khaw)
Newsgroups: comp.sources.bugs
Subject: bug in vn 04/88 rot13
Message-ID: <25303@teknowledge-vaxc.ARPA>
Date: 4 Oct 88 21:01:57 GMT
Reply-To: mkhaw@teknowledge-vaxc.ARPA (Mike Khaw)
Organization: Teknowledge, Inc., Palo Alto CA
Lines: 30

The algorithm used by the vn newsreader to (un)rot13 doesn't work
correctly for every character.  Specifically, I find that "k" and
"m" get mapped to non-printing characters.

I replaced vn's algorithm with the one used by rn.  The fix is really
too short for a patch.  Just replace the rot_line() function in reader.c
with the following version:

<--- cut here --->
static
rot_line (s)
unsigned char *s;
{
	/* short circuit if no rot */
	if (Rot == 0)
		return;

	for ( ; *s != '\0'; ++s)
	{
		/* adapted from rn's rot algorithm */
		*s += isalpha(*s) ? ((*s & 31) <= 13) ? Rot : -Rot : 0;
	}
}
<--- cut here --->

Mike Khaw
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