- Snippet from Wikipedia: Null device
In some operating systems, the null device is a device file that discards all data written to it but reports that the write operation succeeded. This device is called
/dev/null
on Unix and Unix-like systems,NUL:
(see TOPS-20) orNUL
on CP/M and DOS (internally\DEV\NUL
),nul
on OS/2 and newer Windows systems (internally\Device\Null
on Windows NT),NIL:
on Amiga operating systems, andNL:
on OpenVMS. In Windows Powershell, the equivalent is$null
. It provides no data to any process that reads from it, yielding EOF immediately. In IBM operating systems DOS/360 and successors and also in OS/360 and successors such files would be assigned in JCL toDD DUMMY
.In programmer jargon, especially Unix jargon, it may also be called the bit bucket or black hole.