If you can accept a fixed number of fixed sized entries you could (with appropriate locking, of course) make a ring buffer. Store the head and tail offsets as the first record and then use something along the lines of seek( RING, $rec_num * REC_SIZE() + OFFSETSIZE(), SEEK_SET() ) and sysread( RING, $buf, REC_SIZE() ) to retrieve them.

In reply to Re: Shifting the top line(s) of a file? by Fletch
in thread Shifting the top line(s) of a file? by Cody Pendant

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