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Alternative forms[edit]


From Unix operating systems, where /dev (the Unix directory containing device files) contains a null entry representing no device.

Proper noun[edit]


  1. (computing) A device file, present in Unix and Unix-like operating systems, that discards all data written to it and yields no output.
    It's possible to suppress the compiler's warnings by redirecting standard error to /dev/null.
    • 1980 October, Luis F. Cabrera, “A Performance Evaluation Study of UNIX”, in Harold Joseph Highland, editor, Computer Performance Evaluation Users Group 16th Meeting (National Bureau of Standards Special Publication; 500-65), Washington: Government Printing Office, page 235:
      To avoid problems when running the script, the output of man man was sent to /dev/null instead of sending it to a real terminal. This has the effect of discarding the already formatted text of the retrieved page.
    • 1993, Stephen A. Rago, UNIX System V Network Programming, Pearson, →ISBN, page 89:
      [...] we reserve file descriptors 0, 1, and 2 by opening /dev/null and duplicating the file descriptor returned. /dev/null is a pseudo-driver that forces read to return 0 and write to return as if the entire amount requested had been written. This makes library routines that use file descriptors 0, 1, and 2 harmless.
    • 2005, Eric Foster-Johnson; John C. Welch; Micah Anderson, Beginning Shell Scripting, John Wiley & Sons, →ISBN, page 263:
      Continuing in the Unix tradition of treating everything as a file, you can redirect a command's output to the null file, /dev/null. The null file consumes all output sent to it, as if /dev/null is a black hole star.
  2. (Internet slang, figuratively) Nowhere; often suggests an intent to ignore specific correspondence.
    • 1992 September 17, Douglas Meier <dmeier@casbah.acns.nwu.edu>, “Welfare Reform Idea”, in talk.politics.misc, Usenet[1], message-ID <1992Sep17.064757.551@news.acns.nwu.edu>:
      Thoughtful discussion and criticism is welcomed, but please send all flames to dev null.
    • 1993 December 18, Carmien Stefan <carmien@alumni.cs.Colorado.EDU>, “RLP hosed”, in alt.unix.wizards, Usenet[2], message-ID <CI7Gt6.DAo@Colorado.EDU>:
      suddenly the RLP calls form atlanta[sic] apparently go to dev null.
    • 2004 January 17, Ronald D. Edge <InactiveX666@hotmail.com>, “PayPal pyramid scam”, in news.admin.net-abuse.email, Usenet[3], message-ID <SDaOb.873$Ly6.642264@newshog.newsread.com>:
      The email will explicitly state that you cannot reply to the email, it will go to dev null.

Further reading[edit]