Null device

Source: Wikipedia, the free encyclopedia.

In some

JCL
to DD DUMMY.

In programmer jargon, especially Unix jargon, it may also be called the bit bucket[6] or black hole.

History

/dev/null is described as an empty regular file in

Version 4 Unix.[7]

The

Version 5 Unix manual describes a /dev/null device with modern semantics.[8]

Usage

The null device is typically used for disposing of unwanted output streams of a process, or as a convenient empty file for input streams. This is usually done by redirection.

The /dev/null device is a

directory, so one cannot move a whole file or directory into it with the Unix mv
command.

References in computer culture

This entity is a common inspiration for technical

iPhone Dev Team commonly uses the phrase "send donations to /dev/null", meaning they do not accept donations.[9] The fictitious person name "Dave (or Devin) Null" is sometimes similarly used (e.g., "send complaints to Dave Null").[10] In 1996, Dev Null was an animated virtual reality character created by Leo Laporte for MSNBC's computer and technology TV series The Site. Dev/null is also the name of a vampire hacker in the computer game Vampire: The Masquerade – Redemption. A 2002 advertisement for the Titanium PowerBook G4 reads The Titanium Powerbook G4 Sends other UNIX boxes to /dev/null.[11]

The null device is also a favorite subject of technical jokes,[12] such as warning users that the system's /dev/null is already 98% full. The 1995 April Fool's issue of the German magazine c't reported on an enhanced /dev/null chip that would efficiently dispose of the incoming data by converting it to a flicker on an internal glowing LED.

Dev/Null is also the name of an electronic dance music producer and jungle DJ.[13]

See also

Notes

  1. z/VSE
    .
  2. ^ The most recent being z/OS.

References

  1. ^ "Redirecting Error Messages from Command Prompt: STDERR/STDOUT". support.microsoft.com. Retrieved 2020-03-06.
  2. .
  3. ^ "OpenVMS Programming Concepts Manual". h30266.www3.hpe.com. Archived from the original on 2020-07-02. Retrieved 2020-03-06.
  4. ^ SteveL-MSFT. "about_Automatic_Variables - PowerShell". docs.microsoft.com. Retrieved 2020-03-06.
  5. ^ "Single Unix Specification Section 10.1: Directory Structure and Files". The Open Group. Retrieved 2012-11-29.
  6. ^ "bit bucket". Jargon File. Retrieved 2013-12-27.
  7. ^ Thompson, K.; Ritchie, D. M. (November 1973). UNIX Programmer's Manual, Fourth Edition. Bell Telephone Laboratories, Inc. sh (I) (./man1/sh.1). Online at TUHS.
  8. ^ Thompson, K.; Ritchie, D. M. (June 1974). UNIX Programmer's Manual, Fifth Edition (PDF). Bell Telephone Laboratories, Incorporated. mem (IV).
  9. ^ "Dev-Team Blog - Donations to /dev/null". 2015-09-07. Archived from the original on 2015-09-07. Retrieved 2018-11-15.
  10. .
  11. ^ "Image: unixad.jpg, (1094 × 720 px)". Archived from the original on 2013-03-26. Retrieved 2015-09-02.
  12. ^ "The FreeBSD Funnies". Freebsd.org. Retrieved 2012-11-28.
  13. ^ "Dev Null Microjunglizm". The New Yorker. Retrieved 2024-01-24.