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From: bill@ur-cvsvax.UUCP (Bill Vaughn)
Newsgroups: net.bugs
Subject: Awk bug
Message-ID: <222@ur-cvsvax.UUCP>
Date: Thu, 5-Sep-85 18:21:24 EDT
Article-I.D.: ur-cvsva.222
Posted: Thu Sep  5 18:21:24 1985
Date-Received: Sat, 7-Sep-85 06:06:48 EDT
Distribution: net
Organization: Center for Visual Science, U. of Rochester
Lines: 51

A bug in awk which I thought had been fixed seems to have reappeared in
another situation.  It involves the string $0 and how the modification of
individual fields affect it. It seems that the assignment of $0 to a
variable has not been covered by the previous fix. But then, a bare 'print'
statement changes $0 to what one expects it to be!
Check out the following script. (blank lines inserted for readability)

Script started on Thu Sep  5 17:43:58 1985

11> cat /tmp/awks
{$1=""; x[1]=$0; print x[1]}\
{print}\
{y=$0; print y}

12> echo 1 2 3 | awk -f /tmp/awks
1 2 3
 2 3
 2 3

13> cat /tmp/awks1
{$1=""; print}\
{x[1]=$0; print x[1]}\
{y=$0; print y}

14> echo 1 2 3 |awk -f /tmp/awks1
 2 3
 2 3
 2 3

15> cat /tmp/awks2
{$1=""; y=$0; print y}\
{print}\
{x[1]=$0; print x[1]}

16> echo 1 2 3 |awk -f /tmp/awks2
1 2 3
 2 3
 2 3

17> 
script done on Thu Sep  5 17:49:04 1985

Does anybody know whats going on here? If it's relevant, I'm running 4.2bsd
on a 750. Thanks

_________________________________
\         Bill Vaughn           /
 \  Center for Visual Science  /
 /   University of Rochester   \
/   rochester!ur-cvsvax!bill    \
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