ZERO(4D) Devices ZERO(4D)

zero - source of zeroes

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.

/dev/zero

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

July 3, 1990 OmniOS