NAME

zero − source of zeroes

SYNOPSIS

None; included with standard system. 

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(2V), getpagesize(2), mmap(2)

Solbourne Computer, Inc.  —  12 Dec 1990