From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andreas Karlsson <andreas@proxel.se>
cc: John Naylor <jcnaylor@gmail.com>, Stas Kelvich <s.kelvich@postgrespro.ru>,
        Andrew Dunstan <andrew.dunstan@2ndquadrant.com>,
        PostgreSQL Hackers <pgsql-hackers@postgresql.org>,
        David Fetter <david@fetter.org>
Subject: Re: unused_oids script is broken with bsd sed
In-reply-to: <9319.1524749946@sss.pgh.pa.us>
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Thu, 26 Apr 2018 09:39:06 -0400"
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Date: Thu, 26 Apr 2018 10:27:50 -0400
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I wrote:
> Andreas Karlsson <andreas@proxel.se> writes:
>> What about using FindBin (http://perldoc.perl.org/FindBin.html)?

> A quick check suggests that that's present in the core perl
> distribution pretty far back, so I think it'll work.
> Question is, is it any better than John's "dirname(__FILE__)"
> solution?

I experimented a bit, and found that actually what we seem to
need is FindBin::RealBin.  That's the only one of these solutions
that gives the right answer if someone's put a symlink to
unused_oids or duplicate_oids into their PATH --- the other ones
give you the directory containing the symlink.  Now, maybe that
would be an uncommon usage, but it hardly seems out of the question.

			regards, tom lane