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Re: hash array

by liverpole (Monsignor)
on Nov 03, 2010 at 18:01 UTC ( #869285=note: print w/replies, xml ) Need Help??

in reply to hash array

Hi roadtest,

You have a number of issues, all of which are very minor.

For one thing, note that @owner and %owner are separate things (the first is an array, the second a hash), and you don't ever declare the hash:

my %owner = ( );

You should also (though you didn't ask about this) check the return value from open, otherwise (as I did) you could get a confusing error message like "readline() on closed filehandle FILE at C:\test\ line 10".  Here's a simple fix for that:
open (FILE,"cron.log") or die "Can't open 'cron.log -- here's why: + $!\n";
but even better than that is to use the 3-arg open statement instead of the 2-arg version, which (along with lexical filehandles) is considered better programming practice:
use IO::File; my $fh = new IO::File("cron.log", "r") or die "Can't open 'cron.log' ( +$!)\n"; # Now use $fh in place of FILE ...

It might be better to break next if (split /[ ]+/)[1] !~ /oracle|sybase/ ; into multiple lines:

my @split = split /[ ]+/; my $split1 = $split[1] || ""; next if ($split1 !~ /oracle|sybase/)

so that when your input file doesn't contain what you expect, or something else goes wrong, you can debug the values in @split, or the value of $split1 (which might be undefined; hence my converting it to "").

You don't need to do (keys %{$owner} (which you've done in two or three places), it suffices to do (keys %owner) to get the keys of the hash.

Here's a version that runs without warnings:

#!/usr/bin/perl use strict; use warnings; use Date::Manip; use IO::File; my @owner = qw/oracle sybase/; my %owner = ( ); my $fh = new IO::File("cron.log") or die "Can't open 'cron.log' ($!)\n +"; while(<$fh>) { chomp; my @split = split /[ ]+/; my $split1 = $split[1] || ""; next if ($split1 !~ /oracle|sybase/); my ($mode,$owner,$job_id,undef,undef,undef,undef,$timestamp,undef) + = split /[ ]+/; #get same jobID finish timestamp and calculate difference, #then save back ${owner}{$job_id} = DateCalc (${$owner}{$job_id},$timestamp) if ($mode=~ /^>/); } close $fh; foreach my $owner(@owner) { foreach (keys %owner) { print "$owner - JobID:$_ - RunTime:${$owner}{$_}\n"; }; }

Now you can focus on whether the program is working as you wish...


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Re^2: hash array
by roadtest (Sexton) on Nov 05, 2010 at 18:28 UTC
    Thanks for pointing out my bad habit. Points are taken.:-)

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[ambrus]: oh right. kilobits versus kilobytes. confusing.

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