HP X.25/9000 Programmer's Guide

Chapter 3 27

Establishing and Terminating a Socket Connection

Connection Establishment for the Server Process

Connection Establishment for the Server

Process

This section describes the system calls and parameters executed by the

server process to establish a connection.

In the simplest case, there are four steps that the server process must

complete before a connection can be made with a client:

1. Create a socket with socket().

2. Bind an address to the new socket with bind().

3. Add a listen queue to the socket with listen().

4. Wait for an incoming call with accept().

NOTE Take care to avoid issuing contradictory system calls when porting

applications for operation with BSD IPC sockets. You cannot, for

example, issue a connect() call on a socket on which you have

previously issued a bind() call. Conﬂicting system calls will return the

EOPNOTSUPP (223) error message.

Creating a Socket

Before any other BSD IPC system call is executed, the server process

must call socket() to create a BSD IPC socket.

Syntax for socket()

The socket() system call and its parameters are described below.

#include <sys/types.h>

#include <x25/ccittproto.h>

#include <sys/socket.h>

int sd;

int af, type, protocol;

sd = socket(af, type, protocol);

af Identiﬁes the socket’s address family. For X.25 programmatic access, you

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