In this code also if you add one more if condition before doing this calculation,
it will prevent these kind of error if future 
if ($used){ 
my $monit_percentual = (  $avail  /  $avail+$used  ) * 100 ;
    my $final_used = $used / 1000 ;
    my $final_avail = $avail / 1000 ;
    print "$monit is a $fs_type filesystem who has $final_used space u
+sed (in MB) and $final_avail of avalible space (in MB too) \n" ;
    #comparacion con el porcentaje de $monit_percentual
    if ($monit_percentual < $warn) {
            print "Less of the $warn % of the space of the filesystem 
+$monit is avalible for use, consider uninstall unused software \n" ;
    }
    elsif ($monit_percentual eq $warn) {
            print "Be carefull, exactly the $warn % of the space of $m
+onit is usable, consider uninstall unused software \n" ;
    }
    else {
            print "There is a $monit_percentual % of avarible space of
+ the disk \n" ;
    }
}else{
print "Some message\n";
}

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In reply to Re^2: Some help with my project: by madtoperl
in thread Some help with my project: by 0uts1de

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