Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!elroy.jpl.nasa.gov!jarthur!kfink
From: kfink@jarthur.Claremont.EDU (Kevin Fink)
Newsgroups: comp.lang.perl
Subject: Question about dbm files and assoc arrays
Message-ID: <8133@jarthur.Claremont.EDU>
Date: 17 Aug 90 15:38:19 GMT
Organization: Harvey Mudd College, Claremont, CA 91711
Lines: 71

When I upgraded from pl 18 to pl 28, one of my scripts broke. I'm not sure
if the problem is in the patches or in a change in our system, however. The
problem arises when using the dbm functions. The op.dbm test works, but this
script doesn't do what I think it should...

#! /usr/local/binperl

$test = "test";
dbmopen(TEST,$test,0666);

dbmopen(TEST2,$test,0666) || die "ndbm missing"; 
dbmclose(TEST2);

@keylist = keys(%TEST);
@vallist = values(%TEST);
while ($#keylist ne -1)
{
 $key = pop(@keylist);
 $val = pop(@vallist);
 printf "%s\t%s\n",$key,$val;
}

print "1 : ".$TEST{'hello'}."\n";
print "2 : ".$TEST{$key}."\n";
$TEST{'hello'} = "hi";
print "3 : ".$TEST{'hello'}."\n";
dbmclose(TEST);

dbmopen(TEST1,$test,0666);
print "4 : ".$TEST1{'hello'}."\n";
dbmclose(TEST1);


When this script is run, I would expect to get
1 :
2 :
3 : hi
4 : hi
since TEST doesn't contain anything until I assign hi to hello.

When I run it a second time (once the dbm file has
been saved to disk) I would expect to get
hello	hi
1 : hi
2 : hi
3 : hi
4 : hi

However, what I actually get the first time is
1 :
2 :
3 : hi
4 :

and the second time I get
hello hi
1 :
2 :
3 : hi
4 :

So it appears that the assoc array is saved to the dbm file, but either I'm
making a dumb mistake trying to get the value of hello out, or something is
broken.

I'm running perl pl 28 on a Sequent Balance running Dynix 3.0.17.9.

Thanks.

Kevin Fink
kfink@jarthur.claremont.edu