inet_netof Subroutine

Purpose

Returns the network id of the given Internet address.

Library

Standard C Library (libc.a)

Syntax

#include <sys/socket.h>
#include <sys/socketvar.h>
#include <netinet/in.h>
#include <arpa/inet.h>
 
int inet_netof (InternetAddr)
struct in_addr InternetAddr;

Description

The inet_netof subroutine returns the network number from the specified Internet address number typed as unsigned long value. The inet_netof subroutine masks off the network number and the host number from the Internet address based on the Internet address class.

Note: The application assumes responsibility for verifying that the network number and the host number for the Internet address conforms to a class A or B or C Internet address. The inet_netof subroutine processes any other number as a class C address.

Parameters

Return Values

Upon successful completion, the inet_netof subroutine returns a network number from the specified long value representing the Internet address. If the application gives a class A Internet address, the inet_lnoaf subroutine returns the logical product of the Internet address and 0xFF000000 . If the application gives a class B Internet address, the inet_lnoaf subroutine returns the logical product of the Internet address and 0xFFFF0000. If the application does not give a class A or B Internet address, the inet_lnoaf subroutine returns the logical product of the Internet address and 0xFFFFFF00.

Implementation Specifics

The inet_netof subroutine is part of Base Operating System (BOS) Runtime.

All applications containing the inet_netof subroutine must be compiled with _BSD set to a specific value. Acceptable values are 43 and 44. In addition, all socket applications must include the BSD libbsd.a library.

Files

Related Information

The endhostent subroutine, endnetent subroutine, gethostbyaddr subroutine, gethostbyname subroutine, getnetbyaddr subroutine, getnetbyname subroutine, getnetent subroutine, inet_addr subroutine, inet_lnaof subroutine, inet_makeaddr subroutine, inet_network subroutine, inet_ntoa subroutine, sethostent subroutine, setnetent subroutine.

Sockets Overview and Understanding Network Address Translation in AIX Version 4.3 Communications Programming Concepts.