zero(7)                          UNIX System V                          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 sysconf.  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), sysconf(3C), mmap(2)































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