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fork(2)

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zero(7D)

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), mmap(2), sysconf(3C)

SunOS 5.5.1  —  Last change: 3 Jul 1990

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026