On a practical level for beginners, it means:
Don't buffer STDOUT.

Well, yeeeessss. Buffering is still happening. It's just that setting $| to true asks for the buffer to be emptied after each output command (print, printf, etc) rather than wait until a newline or a full buffer is encountered.

In reply to Re: Re: what does '$| = 1' mean? by virtualsue
in thread what does '$| = 1' mean? by Anonymous Monk

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