Hi BrowserUk,

I understood the role of special variable from your notes. I also tried to implement the same in my code. Please find it below:

sub new
{
    my $class   = shift();
    my $self        = {};
    $self->{fname}  = shift() or $self->{fname} = "STDIN";

    print "Inside new in X12.pm\n";

    # Open File Handle
    if ($self->{fname} ne "STDIN")
    {
        # Check For Empty File
        if (not -s $self->{fname})
        {
            #die "Empty or non-existent input file.\n";
            return 0;
        }
        local *IN;
        print "Before File Open\n";
        open(IN, "< $self->{fname}") or return 0; #die "Can't open $se
+lf->{fname} for input: $!\n";
        print "After File Open\n";
        $self->{file} = *IN;
        $self->{fopen} = 1;
    }
    else
    {
        $self->{file} = *STDIN;
    }

    my $line = "";
    while (not length($line))
    {
        print "inside while loop in X12.pm\n";
        $line = readline($self->{file});
        #die "Unexpected EOF in file $self->{fname}\n" if (not defined
+($line));
        return 0 if (not defined($line));
        $line =~ s/^\s+//;  # Strip leading whitespace
        print "line read from the file in X12.pm\n";
    }

    # Get Header Information and Initalize File Read Buffer
    if ($line !~ /^ISA/)
    {
        $self->{fieldOut}   = "*";
        $self->{segOut}     = "\n";
        $self->{compSep}        = "<";
        $self->{fieldSep}   = "\\*";
        $self->{segSep}     = "\\\n";
        print "self in if cond in X12.pm\n";
    }
    elsif (length($line) < 106)
    {
        return 0;
        #die "ISA segment invalid, aborting.\n";
    }
    else
    {
        $self->{fieldOut}   = substr($line, 3, 1);
        $self->{segOut}     = substr($line, 105, 1);
        $self->{compSep}        = substr($line, 104, 1);
        $self->{fieldSep}   = "\\$self->{fieldOut}";
        $self->{segSep}     = "\\$self->{segOut}";
        print "self in else cond in X12.pm\n";
    }

    print "self->{segSep} is $self->{segSep}\n";

    local $/ = $self->{segSep};
#    @{ $self->{lines}} = split(/$self->{segSep}/, $line);
    push @{ $self->{lines}}, $_  while readline($self->{file});
    print "New in X12 complete\n";
    bless($self, $class);
    return $self;
}
[download]

But i dont get the desired results. Am i doing anything wrong? Please let me know.

Thanks,

peacelover1976