here is the problem...i used komodo IDE to modify the code to function properly, and when i run it on the Windows platform, both in and out of a debugger, it works perfectly returning my values as it should... however, when i put this on a linux machine, it returns this message: "Modbus client : problem with recv:" i have not a clue as to what the problem is... any ideas on what it could be would be appreicated...

#!/usr/bin/perl5.8.7
use IO::Socket;
use XML::Simple;
use crctable;
use strict;

use constant MAX_RECV_LEN => 65536;

##################### reading configuration from xml file ############
+#####################

my $xmlfile = 'config.xml';             #Configuration file
my $xs1 = XML::Simple->new();
my $doc = $xs1->XMLin($xmlfile)
or die "Modbus client : problem with congig file: $xmlfile\n";

my $simple_tcp_port = $doc->{SERVER}->{PEERPORT};
my $remote_host = $doc->{SERVER}->{PEERADDR};
my $remote = shift || $remote_host;
my $remote_port = shift || $simple_tcp_port;

my $slave_add = $doc->{REGISTERS}->{SLAVEADDR};
my $start_add = $doc->{REGISTERS}->{STARTADDR}  ;
my $quantity = $doc->{REGISTERS}->{QUANTITY};
my $polls_time = $doc->{REGISTERS}->{POLLSTIME};
my $nr_of_polls = $doc->{REGISTERS}->{NROFPOLLS};
my $data_format = $doc->{REGISTERS}->{DATAFORMAT};
my $meas_scale = $doc->{REGISTERS}->{SCALE};
my $hi_limit = $doc->{REGISTERS}->{HILIMIT};
my $lo_limit = $doc->{REGISTERS}->{LOWLIMIT};

my $trans_serv = getprotobyname( 'tcp' );
$remote_host = gethostbyname( $remote )
or die "Modbus client : name lookup failed: $remote\n";
my $destination = sockaddr_in( $remote_port, $remote_host );
my $start_add_val = pack("n",$start_add);

my $pack_val = unpack("H*", $start_add_val);

my $msg_count = 0;
my $pass;

$quantity < 256 or die "Nr of registers must be less or equal 255\n";

#################### end of configurations ###########################
+##################

#################### Modbus frame ####################################
+###################
my @buffor = ();
$buffor[0] = chr($slave_add);
$buffor[1] = chr(3);
$buffor[2] = chr(hex (substr ($pack_val, 0, 2)));
$buffor[3] = chr(hex (substr ($pack_val, 2, 2)));
$buffor[4] = chr(0);
$buffor[5] = chr($quantity);
##################### end of Modbus frame ############################
+###################



##################### CRC ############################################
+################### 

my $i;
my $index;
my $Length = 6;
my $crc_Low = 0xFF;
my $crc_High = 0xFF;

for ($i = 0; $i<$Length; $i++)

{
our @crc_table;       
$index = ($crc_High ^ ord($buffor[$i]));
$crc_High = $crc_Low ^ $crc_table[$index] ;
$crc_Low = $crc_table[$index + 256];
}
$buffor[6] = chr($crc_High);
$buffor[7] = chr($crc_Low);

##################### end of CRC #####################################
+###################

#################### connecting to the server ########################
+##################

socket( TCP_SOCK, PF_INET, SOCK_STREAM, $trans_serv )
      or die "Modbus client: socket creation failed: $!\n";
my $con_ok = connect( TCP_SOCK, $destination )
      or warn "Modbus client: connect to remote system failed: $!\n";
      next unless $con_ok;

################### server connected #################################
+##################

################### reading registers ################################
+################## 

while ( $msg_count < $nr_of_polls){
        my $data = join('',@buffor);       #Modbus frame to scalar
        
       send( TCP_SOCK, $data, 0 )
              or warn "Modbus client : problem with send: $!\n";



        my $from_who = recv( TCP_SOCK, $data, MAX_RECV_LEN, 0 );
        
        
        if ( $from_who ){                                     #New dat
+a from server 
            
            my ( $the_port, $the_ip ) = sockaddr_in( $destination );
            my $i;
            my ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) =
+ localtime(time); 
            print "\n $hour:$min:$sec  >>  New data from Modbus RTU de
+vice \n";
                 
              for ($i = 0; $i < (length( $data ) - 5)/4; $i++){
                     
                my $hex = substr $data, $i*2+3, 4;
                if ($data_format eq "HEX"){
                  $hex = unpack ("H*", $hex);
                  $hex = unpack "f", reverse pack "H*", $hex ;
                  } 
                else {
                  $hex = unpack "n", $hex;
                  }
                my  $regadd = 1 + $start_add  + $i;
                print " Register $regadd : "; printf("%.3f", $hex); pr
+int " $meas_scale \n";
                if($lo_limit > $hex ){
                            print "Warning limit is below low limit cr
+iteria!\n"
                }elsif($hi_limit < $hex){
                            print "Warning limit is above High Limit C
+riteria!\n"
                     
                }
                
              }

#my $f = 0x42700000;
#my $reg_value = unpack("f", pack("i", $f));
#printf("%.3f", $reg_value);


}
else
{
warn "Modbus client : problem with recv: $!\n";

}

}
continue {
$msg_count++;
sleep($polls_time);
}

close TCP_SOCK
or warn "tcp_c1: close failed: $!\n";
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