null - the null file, also called the null device
Data written on the null special file, /dev/null, is dis-
Reads from a null special file always return 0 bytes.
Mapping a null special file creates an address reservation
of a length equal to the length of the mapping, and rounded
up to the nearest page size as returned by sysconf(3C). No
resources are consumed by the reservation. Mappings can be
placed in the resulting address range via subsequent calls
to mmap with the -MAP_FIXED option set.
Man(1) output converted with