/dev/null

See also: dev null, dev-null, and devnull

English

Alternative forms

• dev null, dev-null, devnull

Etymology

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

Proper noun

/dev/null

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 with John C. Welch and 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^[1] (Usenet), 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^[2] (Usenet), 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^[3] (Usenet), 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.

Hypernyms

device file

• null device
• pseudodevice

 

Coordinate terms

• bit bucket
• black hole

 

Further reading

• null device on Wikipedia.Wikipedia