/dev/null is a character device file on UNIX computer operating systems that accepts all data written to it, without storing it. It can be opened by many processes simultaneously, and writing to it doesn't cause the file to grow. Formally, it's described as being an infinite data sink. In shell programming, unwanted output from a command can be redirected there. For example:more...
find / 2>/dev/null
This would display the full paths to all the accessible files on the computer, without displaying the "Permission denied" errors that are likely to occur.
When programs try to read from /dev/null, they get an end-of-file error.
The idea of a null device was imitated by Microsoft in MS-DOS. In DOS, 'NUL' is a reserved filename. When you open a file with that name, DOS opens its equivalent of /dev/null. This behavior was inherited by Windows. In Windows,
even versions of it that are based on the NT kernel, you cannot create a file called "NUL".
It is usually pronounced as "dev null", not "slash dev, slash null." Programmers sometimes refer to /dev/null as a place to send any unwanted information, even if, for example, the data is being transmitted as spoken words from a human's mouth.
This word comes from a combination of /dev/nul and flux. The root word 'nul' is considered to translate to 'void' or 'absence'. 'Flux' can have different meanings depending on context but in this definition it most closely resembles 'change' or 'modification'. Therefore the combined meaning of the word 'nulflux' is: The absence or void of change; static.
This term was first used by Steven A. Hammock to describe the unfaltering hate he harbors for his stepfather.
"The hatred inside me is in a state of constant nulflux. It never changes."