htonl() — Translate address host to network long

Standards

Standards / Extensions	C or C++	Dependencies
XPG4.2 Single UNIX Specification, Version 3	both

XPG4.2

#define _XOPEN_SOURCE_EXTENDED 1
#include <arpa/inet.h>

in_addr_t htonl(in_addr_t hostlong);

SUSV3

#define _POSIX_C_SOURCE 200112L
#include <apar/inet.h>

uint32_t htonl(uint32_t hostlong);

Berkeley Sockets

#define _OE_SOCKETS
#include <sys/types.h>
#include <arpa/inet.h>
#include <netinet/in.h>

unsigned long htonl(unsigned long a);

The htonl() function translates a long integer from host byte order to network byte order.

Parameter: Description
a: The unsigned long integer to be put into network byte order.
in_addr_t hostlong: Is typed to the unsigned long integer to be put into network byte order.

Notes:

For MVS™, host byte order and network byte order are the same.
Since this function is implemented as a macro, you need one of the feature test macros and the inet header file.

htonl() returns the translated long integer.