Debian bug report logs - #737
gawk references to `$0' in END rule give previous record

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Date: Tue, 4 Apr 95 13:01 BST
From: iwj10@cus.cam.ac.uk (Ian Jackson)
To: Debian bugs submission address <debian-bugs@pixar.com>
Subject: gawk references to `$0' in END rule give previous record

Package: gawk
Version: 2.15.6-1

chiark:~/junk> cat t
BEGIN   { print "begin rule here >", $0, "<"; }
/./     { print ". rule here >", $0, "<"; }
END     { print;
          print "end rule just done >", $0, "<"; }
chiark:~/junk> /usr/bin/awk -f t </etc/host.conf 
begin rule here >  <
. rule here > order hosts,bind <
. rule here > multi on <
multi on
end rule just done > multi on <
chiark:~/junk> cat /etc/host.conf 
order hosts,bind
multi on
chiark:~/junk> 

As you can see, the `print' and `print "end rule ..."' statements are
using the value of $0 for the last record.

However, according to the gawk info file (node BEGIN/END, at the very
bottom):
    `BEGIN' and `END' rules must have actions; there is no default
 action for these rules since there is no current record when they run.

This implies that $0 should be empty.

I discovered this bug when trying to build the latest version of the
smail package.  It contains an awk script that does a bare `print' in
the END rule, expecting a blank line, but instead gets the final line
of the input file.  This causes the build to fail.

Ian.