A few comments:

You never use $check. One thing I've taken on as a habit is to declare the variables I use as 'my' when I use them. When you pre-declare them in one string as you have with my ($ua, $req, $chrom, $start, $end, $db, $check);, you increase the chance of error when you remove/add them later, as you have in this script. One possible solution is as follows: 

my $ua          = LWP::UserAgent->new;
my $chrom       = "7";
my $start       = "117287204";
my $end         = "117475903";
my $db          = "hg11";
my $url         = "http://genome.ucsc.edu/cgi-bin/hgText";

[download]
(I also like to indent for readability, but that's more a matter of personal style.)

You also are not properly separating your POST object. It should look something like: 

# Indented again
my $request     = POST $url,
        ['hgsid'        => "6765675",
         'g'            => "htcGetDna2",
         'c'            => 'chr'.$chrom,
         'l'            => $start,
         'r'            => $end,
         'db'           => $db,
         'hgc.dna.out1' => 'lc',
         'boolshad.hgc.dna.rc' => '1',
         'Submit'       => 'Submit'
        ];

[download]
Note the use of the single quotes around the key, which was missing in your original script. Adding the above fixes allows your code to work as intended.

In reply to Re: LWP and barewords under strict by hacker
in thread LWP and barewords under strict by Bukowski

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