I'm not sure I really understand what you're asking for.
I have several questions/comments, though :
  • if you want to split with a pipe, you need to escape the pipe, since the pipe is a special character in regex : split /\t/, $_;
  • $GU doesn't exist; you probably mean $GU_web.
  • structure_name is supposed to be a variable, you forgot "$", and you have a ">" which isn't supposed to be there.
  • What's in your "gly_structures.txt" ? I mean, can there be duplicate $ref_num ?
  • Why do you have this loop for ? 
    $i=1;
while (<info_web>) {
   if (/^(\d+\.\d+)\D/) {$GU_web = $1;}
   if ($i >1) { last;}
   print "$GU_web\n";
   $i++;  
}

    [download]
    You're going through it only twice, assigning what you captured in the regex to $GU_web twice, and printing $GU_web only once.

    In reply to Re: cgi question by Tomtom
    in thread cgi question by Anonymous Monk

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