Strange DBM behavior

Stamp_Guy has asked for the wisdom of the Perl Monks concerning the following question:

Hello,
I've got a problem with the following DBM script I'm working on. I'm running on a server with perl version 5.003_02 + two suidperl security patches. I get the following error: No write permission to ndbm file at pl.pl line 16. Instead of the typical two files that this script generates on my home computer, it generates one file called pricelist.db. I can't chmod it either. What's wrong???

#!/usr/bin/perl5
use CGI::Carp qw(fatalsToBrowser);

use strict;

open(PL, "pricelist.txt") || die "Can't open pricelist";
my @pl = <PL>;
close(PL);

my %PL = ();
dbmopen(%PL, "pricelist", 0777) || die "Can't open pricelist DBM: $!";

for(@pl) {
my @split = split /\|/;
chomp($split[-1]);
if (defined($PL{$split[1]})) {
    $PL{$split[1]} = "$PL{$split[1]}|$split[2],$split[3]";
}

else {
    $PL{$split[1]} = "$split[2],$split[3]";

}
}
my $count = 0;
print "There are ", scalar keys %PL, "items in the DB.\n";
dbmclose(%PL);
[download]

Comment on Strange DBM behavior Select or Download Code

Replies are listed 'Best First'.
Re: Strange DBM behavior by andreychek (Parson) on Jul 03, 2001 at 20:59 UTC
This definitely sounds like a permissions issue as opposed to a Perl issue, but a little more information might be helpful. You mentioned about chmod'ing a file, so I'll assume you're using UNIX/Linux. You're using CGI::Carp, so I'll assume you're using this under a browser, and not running it by hand or via cron. Which probably means you're using Apache (since netcraft claim 62% of the net is using that anyway :-) It sounds like what you need to do is verify that the directory your db files are in are writable by the user which Apache is running as, which would often be 'apache' or 'nobody' on a UNIX-like system. Additionally, make sure the pricelist.db is writable by that same user. If it isn't, it would block you from being able to access that DB, such as what is happening right now. Since you are unable to chmod it, you may have to do it as root. If you don't have root access, just ask your admin to make those dirs/files writable by the Apache process. -Eric	[reply]
Re: Strange DBM behavior by Stamp_Guy (Monk) on Jul 03, 2001 at 21:18 UTC
I did another test to see if I could read from it, but no such luck. Here's what I got: #!/usr/bin/perl5 use CGI qw(:standard); use CGI::Carp qw(fatalsToBrowser); my $cgi = new CGI; use strict; my @scott = $cgi->param('scott'); print "Content-type: text/html\n\n"; my %PL; dbmopen(%PL, "pricelist", 0777) \|\| die "Can't open pricelist DBM: $!"; foreach my $scott (@scott) { if ($scott ne "") { if (defined $PL{$scott}) { my @split = split(/\\|/, $PL{$scott}); for(@split) { my ($description,$price) = split/,/; print "Scott: $scott\t$description\t$price\n"; } } else { print "Scott number $scott not found\n"; } } } dbmclose(%PL); [download] Here's the error I get: `Software error: Missing $ on loop variable at blah blah blah/access.pl line 10.` [download]	[reply] [d/l] [select]
Re: Re: Strange DBM behavior by davorg (Chancellor) on Jul 04, 2001 at 01:42 UTC
That's got nothing to do with your DBM problems. That just means that your version of Perl doesn't support the `foreach my $var (@arr)` syntax. Get a newer version of Perl. -- <http://www.dave.org.uk> Perl Training in the UK <http://www.iterative-software.com>	[reply]


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