Why open in a pipe at all? something like this basicly implements tail in perl:

open (TAIL, "logfile.log");
seek (TAIL, 0, 2); # check the manpage
for (;;) {
  sleep 1; # so we don't hog cpu
  if (seek(TAIL,0,1)) { 
    while (<TAIL>) {
      # code to act on logfile here
    }
  }
  # execution continues here
}
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