different results from the same sub

tcf03 has asked for the wisdom of the Perl Monks concerning the following question:

I have been dillegently working on my first module, while testing it - I noticed a discrepancy in the values it returns depending on how its called. Here is my module code

use strict;
use IO::Socket::INET;
use Socket;
use Carp;
package mship;
##############
sub connection
##############
{
    my $IP          = shift;
    my $TCP_PORT    = shift;

    my ( $ipadd, $port_name, $remote_name );

    $ipadd       = Socket::inet_aton($IP) or
                      croak "$IP is not valid\n";
    $port_name   = getservbyport($TCP_PORT, 'tcp') or
                      $port_name = "unknown";
    $remote_name = gethostbyaddr( $ipadd, 2 ) or
                      croak "Unable to resolve hostname for $IP\n";

    my %stats = ( 'IP'          => $IP,
                  'PORT'        => $TCP_PORT,
                  'port_name'   => $port_name,
                  'remote_name' => $remote_name,
                  'status'      => &stat($IP, $TCP_PORT) );
    print "sub connection port = $TCP_PORT IP = $IP\n";
    return %stats or
        croak "unable to return the value of \%stats\n";;
}
#############
sub stat
#############
{
    ( $ip, $tcp_port ) = @_;
    my $status   = "Up";
    my $sock     = IO::Socket::INET ->new(
                                      Timeout  => 5,
                                      PeerAddr => $ip,
                                      PeerPort => $tcp_port,
                                      Proto    => 'tcp' ) or
                                      $status  = "Down";
    return ($status, $tcp_port, $ip);
        croak "Unable to return the value of \$status\n";
}

1;
[download]

and this is how im calling it

#!/usr/bin/perl -w
use strict;

require "mship.pm";
my %stats = mship::connection('xxx.19.208.27', '9101');

while (my ($key, $value) = each(%stats))
{
    print "$key = $value\n";
}

my $status = mship::stat->('xxx.19.208.27', '9101');
print "\nStatus is $status\n";
[download]

and here are my results

port_name = unknown
remote_name = r_dairy.xxx.com
status = Up
IP = xxx.19.208.27
PORT = 9101

Status is Down
[download]

if I use port 80 in my test both calls report up.

any ideas, as to where I should look?

UPDATE
Im an idiot. I was making changes to a local file called mship.pm and mship.pm was installed. Here is the code - and it works fine...

use strict;
use IO::Socket::INET;
use Socket;
package mship;
##############
sub connection
##############
{
    my $IP          = shift;
    my $TCP_PORT    = shift;

    my ( $ipadd, $port_name, $remote_name );

    $ipadd       = Socket::inet_aton($IP) or
                      die "$IP is not valid\n";
    $port_name   = getservbyport($TCP_PORT, 'tcp') or
                      $port_name = "unknown";
    $remote_name = gethostbyaddr( $ipadd, 2 ) or
                      die "Unable to resolve hostname for $IP\n";

    my %stats = ( 'IP'          => $IP,
                  'PORT'        => $TCP_PORT,
                  'port_name'   => $port_name,
                  'remote_name' => $remote_name,
                  'status'      => &mstat($IP, $TCP_PORT) );
    print "sub connection port = $TCP_PORT IP = $IP\n";
    return %stats or
        die "unable to return the value of \%stats\n";;
}
#############
sub mstat
#############
{
    my ( $ip, $tcp_port ) = @_;
    my $status   = "Up";
    my $sock     = IO::Socket::INET ->new(
                                      Timeout  => 5,
                                      PeerAddr => $ip,
                                      PeerPort => $tcp_port,
                                      Proto    => 'tcp' ) or
                                      $status  = "Down";
    return ($status);
        die "Unable to return the value of \$status\n";
}

1;
[download]

Ted
--
"That which we persist in doing becomes easier, not that the task itself has become easier, but that our ability to perform it has improved."
--Ralph Waldo Emerson

Comment on different results from the same sub Select or Download Code

Replies are listed 'Best First'.
Re: different results from the same sub by ikegami (Patriarch) on Jun 17, 2005 at 20:03 UTC
Your module doesn't even compile. How could it have given that output? Below, I BUG: Changed `mship::stat->(...)` to `mship::stat(...)`. (This is the answer to your question.) BUG: Moved `package mship;`. `croak` was being imported into the wrong namespace. BUG: Added missing `my` in `stat`. BUG: Removed the `croak`s after the `return`s. `return` never fails, so the `croak`s would never be reached. Renamed `stat` to `accepts_conn` to avoid confusion with the builtin function `stat`. Changed to `require "mship.pm";` to `use mship;` Returned a better result from `accepts_conn` (formerly `stat`). (Save the conversion to strings for when it's time to print. Work with true and false until then.) Uppercase variable names are usually constants. Changed the case of `connection`'s arguments. Simplified `$port_name = A or $port_name = B;` to `$port_name = A or B;`. Added spacing so I could see what I was doing. Is confused as to the purpose of `connection`. use strict; package mship; use IO::Socket::INET; use Socket; use Carp; ############## sub connection ############## { my ( $ip, $tcp_port ) = @_; my $ipadd = Socket::inet_aton($IP) or croak "$IP is not valid\n"; my $port_name = getservbyport($TCP_PORT, 'tcp') or "unknown"; my $remote_name = gethostbyaddr( $ipadd, 2 ) or croak "Unable to resolve hostname for $IP\n"; my %stats = ( 'ip' => $ip, 'port' => $tcp_port, 'port_name' => $port_name, 'remote_name' => $remote_name, 'status' => accepts_conn($IP, $TCP_PORT) ? "Up" : "Down" ); print "sub connection port = $TCP_PORT IP = $IP\n"; return %stats; } ############# sub accepts_conn ############# { my ( $ip, $tcp_port ) = @_; my $sock = IO::Socket::INET ->new( Timeout => 5, PeerAddr => $ip, PeerPort => $tcp_port, Proto => 'tcp', ); return $sock ? 1 : 0; } 1; [download] `#!/usr/bin/perl -w use strict; use mship; my %stats = mship::connection('xxx.19.208.27', '9101'); while (my ($key, $value) = each(%stats)) { print "$key = $value\n"; } print "\n"; my $status = mship::accepts_conn('xxx.19.208.27', '9101') ? "Up" : "Do +wn"; print("Status: $status\n");` [download]	[reply] [d/l] [select]
Re: different results from the same sub by japhy (Canon) on Jun 17, 2005 at 19:46 UTC
`mship::stat->('xxx.19.208.27', '9101');` should be written as `mship::stat('xxx.19.208.27', '9101');`. Jeff `japhy` Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and `perl` hacker How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart	[reply] [d/l] [select]