in reply to What the heck does $|++; do?

What the heck does $|++; do?
It makes your output pipe piping hot. See perldoc perlvar.

This is useful for interactive programs that prompt on STDOUT, and read from STDIN. Usually you want the user's cursor to stay on the same line as the prompt. But, the default action of print is to wait until it has a complete line (with \n) before writing it out. Setting $| to 1 changes this behaviour.

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