zero(7)

NAME
     zero - source of zeroes

DESCRIPTION
     A zero special file is a source of zeroed unnamed memory.

     Reads from a zero special file always return a buffer full of zeroes.
     The file is of infinite length.

     Writes to a zero special file are always successful, but the data written
     is ignored.

     Mapping a zero special file creates a zero-initialized unnamed memory
     object of a length equal to the length of the mapping and rounded up to
     the nearest page size as returned by getpagesize(2).  Multiple processes
     can share such a zero special file object provided a common ancestor
     mapped the object MAP_SHARED.

FILES
     /dev/zero

SEE ALSO
     fork(2), mmap(2)