Wikipedia:Reference desk/Archives/Computing/2017 September 5

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September 5

Tape drives as named pipes

In the days when tape drives were secondary rather than tertiary storage, did any of them have separate read and write heads and allow the read head to run a few thousand bytes behind the write head, thus serving as named pipes with the additional benefit of backing up the most recently-read few thousand bytes (assuming the computers they were connected to allowed block-level access)? NeonMerlin 01:28, 5 September 2017 (UTC)

I couldn't find anything in Tanenbaum. Regardless, it's unclear how this would work or what it would accomplish. There may exist tons of (anonymous) pipes and FIFOs at any moment in the system. Their semantics don't require them to be seekable, either (in fact, even in modern Linux, they aren't.) Whatever buffering there is, as I understand it, is solely in order to accommodate atomic writes to the pipe but there's always the option to suspend the write()ing process until someone reads from the pipe. 80.171.95.62 (talk) 05:04, 6 September 2017 (UTC)