You might like to read Mark Jason Dominus's "Suffering From Buffering" at http://perl.plover.com/FAQs/Buffering.html . Perl normally buffers output so it doesn't make a system call for every bit of output. By saving up output, it makes fewer expensive system calls. For instance, in this little bit of code, you want to print a dot to the screen for every line you process to watch the progress of yo