#!/usr/bin/perl 
$xtlsstr = "xtlsstr";
open(XTL, "| $xtlsstr")          # <-- Pipe to the program.
or die("Can't run xtls: $!\n");  # <-- Check for errors.
print XTL "1ax8.pdb\n";          # <-- Don't forget the \n.
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