BSD Sockets Interface Programmer's Guide

40 Chapter 2
Using Internet Stream Sockets
Writing the Client Process
Writing the Client Process
This section explains the calls your client process must make to connect
with and be served by a server process.
Creating a Socket
The client process must call socket to create a communication endpoint.
socket and its parameters are described in the following table.
Include files: #include <sys/types.h>
#include <sys/socket.h>
System call: s = socket(af, type, protocol)
int af, type, protocol;
Function result: socket number (HP-UX file descriptor), –1 if failure
occurs.
Example:
s = socket (AF_INET, SOCK_STREAM, 0);
The socket number returned is the socket descriptor for the newly
created socket. This number is an HP-UX file descriptor and can be used
for reading, writing or any standard file system calls after a BSD Sockets
connection is established. A socket descriptor is treated like a file
descriptor for an open file.
When to Create Sockets
The client process should create sockets before requesting a connection.
Refer to the socket(2) man page for more information on socket.
Parameter Description of Contents INPUT Value
af address family AF_INET
type socket type SOCK_STREAM
protocol underlying protocol to be
used
0 (default) or value
returned by
getprotobyname