BYTEORDER

Section: Linux Programmer's Manual (3)
Updated: 2017-09-15
Page Index

NAME

htonl, htons, ntohl, ntohs - convert values between host and network byte order

SYNOPSIS

#include <arpa/inet.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

The htonl() function converts the unsigned integer hostlong from host byte order to network byte order.

The htons() function converts the unsigned short integer hostshort from host byte order to network byte order.

The ntohl() function converts the unsigned integer netlong from network byte order to host byte order.

The ntohs() function converts the unsigned short integer netshort from network byte order to host byte order.

On the i386 the host byte order is Least Significant Byte first, whereas the network byte order, as used on the Internet, is Most Significant Byte first.

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
htonl(), htons(), ntohl(), ntohs()	Thread safety	MT-Safe

CONFORMING TO

POSIX.1-2001, POSIX.1-2008.

Some systems require the inclusion of <netinet/in.h> instead of <arpa/inet.h>.

COLOPHON

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