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BYTEORDER(3) FreeBSD Library Functions Manual BYTEORDER(3)
NAME
htonl, htons, ntohl, ntohs - convert values between host and network byte
order
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <arpa/inet.h>
or
#include <netinet/in.h>
uint32_t
htonl(uint32_t hostlong);
uint16_t
htons(uint16_t hostshort);
uint32_t
ntohl(uint32_t netlong);
uint16_t
ntohs(uint16_t netshort);
DESCRIPTION
These routines convert 16 and 32 bit quantities between network byte
order and host byte order. On machines which have a byte order which is
the same as the network order, routines are defined as null macros.
These routines are most often used in conjunction with Internet addresses
and ports as returned by gethostbyname(3) and getservent(3).
SEE ALSO
gethostbyname(3), getservent(3), byteorder(9)
STANDARDS
The byteorder functions conform to IEEE Std 1003.1-2001 ("POSIX.1").
HISTORY
The byteorder functions appeared in 4.2BSD.
BUGS
On the VAX bytes are handled backwards from most everyone else in the
world. This is not expected to be fixed in the near future.
FreeBSD 14.0-RELEASE-p11 March 20, 2005 FreeBSD 14.0-RELEASE-p11