ZERO(7)             RISC/os Reference Manual              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 spe-
     cial file object provided a common ancestor mapped the
     object MAP_SHARED.

FILES
     /dev/zero

SEE ALSO
     fork(2), mmap(2), sysconf(3C).































                        Printed 11/19/92                   Page 1