Special device files |
---|
/dev/null
on Unix and Unix-like systems, NUL:
or NUL
on CP/M and DOS (internally DEVNUL
), nul
on newer Windows systems[1] (internally DeviceNull
on Windows NT), NIL:
on Amiga operating systems,[2] and NL:
on OpenVMS.[3] In Windows Powershell, the equivalent is $null
.[4] It provides no data to any process that reads from it, yielding EOF immediately.[5] In IBM DOS/360, OS/360 (MFT, MVT), OS/390 and z/OS operating systems, such files would be assigned in JCL to DD DUMMY
./dev/null
device is a special file, not a directory, so one cannot move a whole file or directory into it with the Unix mv
command./dev/null
', 'my mail got archived in /dev/null
', and 'redirect to /dev/null
'—being jocular ways of saying, respectively: 'don't bother sending complaints', 'my mail was deleted', and 'go away'. The 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]/dev/null
is already 98% full. The April Fool's, 1995 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.dbcc_size
dbcc_devicetype
dbcc_reserved
dbcc_classguid
dbcc_name
Minimum supported client | Windows XP |
Minimum supported server | Windows Server 2003 |
Header | dbt.h |