ZERO(7D) Devices ZERO(7D)
zero - source of zeroes
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
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 sysconf
. Multiple processes can
share such a zero special file object provided a common ancestor mapped
the object MAP_SHARED
SEE ALSO fork(2)
July 3, 1990 ZERO(7D)