Tangent Unfortuenetly there is no output. Also now I am unable to get device name now. I am pasting changed code again.I have tried putting debug statement as well but no output.Please let me know if it is correct. I a really thankful to you that you are giiving your preciosu time to me.

sub updatedevice() {
my $n = {};
my %count;

my $Device_LINK = $server->object("ICF_PersistentDataSet",$devicelinks
+);
my $Temp_Device_LINK = $server->object("ICF_PersistentDataSet",$tempde
+vicelinks);

my @current_devicelist = @{ $Device_LINK->invoke("get") };
my @temp_devicelist = @{ $Temp_Device_LINK->invoke("get") };

my %temp_list;
my %current_list;


my $size = @current_list;
for ($n=0; $n < $size; $n++) {
       our $device=$current_list[$n][0];
    $count{$device}++;
                }
        DEBUG( "DEBUG: - devicelinks  values $device  " );  
               
my $size = @temp_list;
for ($n=0; $n < $size; $n++) {
      our $tempdevicelinks=$temp_list[$n][0];
    $count{$tempdevicelinks}++;   
             }
DEBUG( "DEBUG: - temp plc links values $tempdevicelinks " ); 


my @difference = grep { $count{$_} == 1 } keys %count;
my @intersect  = grep { $count{$_} == 2 } keys %count;
my @union      = keys %count;

#DEBUG( "DEBUG Difference:\n");
#DEBUG( "DEBUG: - $_\n for @difference" );
#DEBUG( "DEBUG: - Intersect:\n ");
#DEBUG( "DEBUG: - $_\n for @intersect ");
#DEBUG( "DEBUG: - Union:\n ");
#DEBUG( "DEBUG: - $_\n for @union " );

print "Difference:\n";
print "$_\n" for @difference;
print "Intersect:\n";
print "$_\n" for @intersect;
print "Union:\n";
print "$_\n" for @union;
[download]

Where does @current_list and @temp_list come from? They seem to be global variables declared elsewhere in your script. To see what they actually contain use Data::Dumper to print them out, and do the same for @current_devicelist and @temp_devicelist. Insert this code and come back with the results - and don't forget to use code tags:

use Data::Dumper;

test_updatedevice();

sub test_updatedevice {
    print Dumper(\@current_list);
    print Dumper(\@temp_list);

    my $Device_LINK = 
        $server->object("ICF_PersistentDataSet",$devicelinks);
    my $Temp_Device_LINK = 
        $server->object("ICF_PersistentDataSet",$tempdevicelinks);
    
    my $current_devicelist = $Device_LINK->invoke("get");
    my $temp_devicelist = $Temp_Device_LINK->invoke("get");
    
    print Dumper($current_devicelist);
    print Dumper($temp_devicelist);
}
[download]

You are genious !!!! Thank you sooo Muchh Tanget ...My issue resolved... Thanks for yout time...