Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!bloom-beacon!usc!orion.cf.uci.edu!uci-ics!zardoz!dhw68k!david
From: david@dhw68k.cts.com (David H. Wolfskill)
Newsgroups: comp.mail.uucp
Subject: Re: Eeek! Pathalias error!
Summary: pathalias 'a = b' notation means "treat 'a' and 'b' as equivalent"
Keywords: incorrect-output
Message-ID: <23188@dhw68k.cts.com>
Date: 25 May 89 03:43:59 GMT
References: <601@acheron.UUCP>
Reply-To: david@dhw68k.cts.com (David H. Wolfskill)
Organization: Wolfskill & Dowling residence; Anaheim, CA (USA)
Lines: 67

In article <601@acheron.UUCP> clarke@acheron.UUCP (Ed Clarke) writes:
>I tried to send mail to "igb@Fulcrum.BT.CO.UK" and my mail went off to
>a fulcrum hanging off of splut.  Here's the pathalias output from my
>current map run:

>fulcrum	bywater!uunet!sugar!splut!fulcrum!%s	420
>fulcrum.bt.co.uk	bywater!uunet!sugar!splut!fulcrum!%s	420

>The u.gbr.1 entry for fulcrum looks ok; the only other entry for
>a fulcrum is a direct link to splut in u.usa.tx.2.  That fulcrum
>has no direct entry in the maps....

Short answer:  Functioning as designed.

Somewhat longer (and possibly more useful) answer:

The map entry in u.gbr.1 for fulcrum includes the lines:

fulcrum	.fulcrum.bt.co.uk
fulcrum = "fulcrum.bt.co.uk"

The second line in that part of the entry tells pathalias to treat
"fulcrum" and "fulcrum.bt.co.uk" as equivalent names for the same
destination.

Now, given that pathalias has been told that, if you then also tell
pathalias

splut		fulcrum(DIRECT)

then pathalias will have also been informed that "splut" has a DIRECT
link to the site that may be known as either "fulcrum" or
"fulcrum.bt.co.uk".

Rather than attempting to spell out a moral to all this, I will merely
point out that I sometimes find it useful to run pathalias on small
samples of (what is intended to be) pathalias input.  This process will
check for syntax errors; it will also perform somewhat of a "reality
check" on the topography that you've specified.

For example, let's contruct some pathalias data based on the above, then
feed it to "pathalias -i -c -l foo" and see what the result is....

First, the input:

fulcrum	.fulcrum.bt.co.uk
fulcrum = "fulcrum.bt.co.uk"
splut	fulcrum(DIRECT)
foo	splut(DEMAND), bar(DIRECT)

Here's the output:

0	foo	%s
200	bar	bar!%s
300	splut	splut!%s
500	fulcrum	splut!fulcrum!%s
500	fulcrum.bt.co.uk	splut!fulcrum!%s
4500	.fulcrum.bt.co.uk	splut!fulcrum!%s

The above results should have a recognizable similarity to the issue
that prompted this discussion.

Hope that helps clarify things a bit,
david
-- 
David H. Wolfskill
uucp: ...{spsd,zardoz,felix}!dhw68k!david	InterNet: david@dhw68k.cts.com