Hardly surprising. You have:

no warnings "all";
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See warnings. You don't check that you're opening files successfully , see open, check $!. To write to your file use:

print OFILE "$name\n";
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Try adding:

use strict;
use warnings;
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Declare your variables, change how you're using open as per the documentation. It looks like you could benifit from learning the basics:

• perlintro
• http://learn.perl.org
• http://perldoc.perl.org
• The tutorials section of this site, including PerlMonks for the Absolute Beginner

Just to be a little more explicit, you don't want to reopen the file every iteration of your loop. There's no reason to reopen it each time you're about to print. So open it before you start reading the input and writing it out.

G'day rocketperl,

"But iam not getting any errors or output with this."

That's not overly surprising as you've turned off all warnings with:

no warnings "all";
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Also, you haven't used strict (which would have provided some output) and you're not checking whether you're IO is working. I'd recommend you start your script like this:

#!/usr/bin/perl
use strict;
use warnings;
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Next take a look at open. See how the two examples at the start of the page end in:

... or die "cannot open ...: $!";
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This gives feedback if there were problems opening the file. Also note the 3-argument form with my $fh which is preferable to the 2-argument form you're currently using. An alternative to hand-crafting these messages for each open is to use autodie.

Once you make these changes to your code, you'll get some feedback. You may be able to fix the problems yourself. If you don't understand the messages, you can get more verbose output with diagnostics.

If, after all that, you're still stuck, post again with the output you get and I'm sure someone will be able to help.

Thanks so much. It worked and got my output!

Slightly abbreviated; syntax and logic problems fixed... and it works for me.

#!/usr/bin/perl
use 5.016;
use strict;
use warnings;
# no warnings "all";    # WHY? warnings are to help you get a compilab
+le program

# 1041200

open (OFILE, '>', 'name.tsv') or die "Can't open for output, $!";  # C
+HECK opens

while (<DATA>) {
    chomp;
    my ($name, $ID, $chromosome, $start_location, $control_type) = spl
+it("\t");
    print "$name \n";
    # open (OFILE, '>name.tsv');   # OPENING HERE OVERWRITES PREVIOUS 
+ENTRY EACH TIME THRU
    print OFILE "$name\n";         # HANDLE and LIST WERE REVERSED
}

__DATA__
fred    123    GeeWhiz    00    freak
jack    4321    Whoosh    04    paternalist
sam    9876    imme    27    passive
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Hello rocketperl,

You are opening the filehandle OFILE for writing on each loop iteration. That truncates the file every time! You need to open OFILE once only, before the while loop starts, and then print to it as marto has shown.

Update: As ww points out, it might be clearer to say that when you (re-)open an existing file for writing, you will then be overwriting whatever was there before. Although open uses the term “truncate” in this context, this should not be confused with Perl’s truncate function which reduces a file to a given length.

Hope that helps,