Select Code to Download

sub find_between_tags($$$) {
  # pass me the string to parse, the start tag, and the end tag
...
}

print find_between_tags($stuff, "START", "STOP");

Benchmark: timing 100000 iterations of mine, original...
      mine:  4 wallclock secs ( 3.28 usr +  0.00 sys =  3.28 CPU) @ 30
+534.35/s (n=100000)
  original: 14 wallclock secs (13.12 usr +  0.00 sys = 13.12 CPU) @ 76
+22.53/s (n=100000)