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Unix manual page for swab. (host=minya system=Darwin)
SWAB(3) BSD Library Functions Manual SWAB(3)
NAME
swab -- swap adjacent bytes
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
void
swab(const void *restrict src, void *restrict dest, ssize_t nbytes);
DESCRIPTION
The function swab() copies nbytes bytes from the location referenced by
src to the location referenced by dest, swapping adjacent bytes.
The argument nbytes should be an even number. If nbytes is odd, swab()
copies and exchanges nbytes -1 bytes and the disposition of the last byte
is unspecified. If copying takes place between objects that overlap, the
behavior is undefined. If nbytes is negative, swab() does nothing.
SEE ALSO
bzero(3), memset(3), compat(5)
HISTORY
A swab() function appeared in Version 7 AT&T UNIX.
BSD February 24, 2010 BSD