zero(7)                                                             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 MAPSHARED.

   FILES
         /dev/zero

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






























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