TCP/IP Sockets in C: Practical Guide for Programmers

147 Pages·2005·6.36 MB·English

TCP/IP Sockets in C
Practical Guide for Programmers
The Morgan Kaufmann Practical Guides Series
Series Editor: Michael J. Donahoo
TCP/IP Sockets in C: Practical Guide for Programmers
Michael J. Donahoo and Kenneth L. Calvert
TCP/IP Sockets in Java: Practical Guide for Programmers
Kenneth L. Calvert and Michael J. Donahoo
JDBC: Practical Guide for Java Programmers
Gregory D. Speegle
For further information on these books and for a list of forthcoming titles,
please visit our Web site at www.mkp.com/practical.
TC P /I P SOC kets i n C
Practical G u ide for Prog ram me rs
Michael J. Donahoo
Baylor University
Kenneth L. Calvert
University of Kentucky
l ~ ~4 ~
MORGAN K A U F M A N N P U B L I S H E R S
An Imprint of Elsevier
SAN FRA N C I S C O SAN D I E G O N E W Y O R K B O S T O N
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Morgan Kaufmann Publishers
An Imprint of Elsevier
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�9 2001 by Elsevier USA
All rights reserved.
Printed in the United States of America
Originally published as The Pocket Guide to TCP/IP Sockets: C Version (1-55860-686-6)
06 05 5
No part of this publication may be reproduced, stored in a retrieval system, or
transmitted in any form or by any means-electronic, mechanical, photocopying, or
otherwise-without the prior written permission f the publisher.
Library of Congress Control Number: 2001095844
ISBN-13:978-1-55860-826-9 ISBN-10:1-55860-826-5
This book is printed on acid-free paper.
For Lisa and Tricia.
This Page Intentionally Left Blank
Contents
Preface xi
PART 1 Tutorial 1
1 Introduction 3
1.1 Networks, Packets, and Protocols 3
1.2 About Addresses 5
1.3 Clients and Servers 6
1.4 What Is a Socket? 7
Thought Questions 8
2 Basic Sockets 9
2.1 Creating and Destroying 9
2.2 Specifying Addresses 10
2.3 TCP Client 1 2
2.4 TCP Server 17
Thought Questions 23
3 Constructing Messages 25
3.1 Encoding Data 26
3.2 Byte Ordering 28
3.3 Alignment and Padding 30
3.4 Framing and Parsing 31
Thought Questions 33
vii
viii Contents �9
Using UDP Sockets 35
4.1 UDPClient 36
4.2 UDP Server 39
4.3 Sending and Receiving with UDP Sockets 41
Thought Questions 42
Socket Programming 43
5.1 Socket Options 43
5.2 Signals 44
5.3 Nonblocking I/O 50
5.4 Multitasking 60
5.5 Multiplexing 72
5.6 Multiple Recipients 77
Thought Questions 85
6 Under the Hood 87
6.1 Buffering and TCP 89
6.2 Deadlock 91
6.3 Performance Implications 92
6.4 TCP Socket Life Cycle 93
6.5 Demultiplexing Demystified 100
Thought Questions 102
Domain Name Service 103
7.1 Mapping Between Names and Internet Addresses 104
7.2 Finding Service Information by Name 106
PART 2 API Reference 109
API Reference 111
Data Structures 111
sockaddr 111
sockaddr_in 111
Socket Setup 112
socket() 112
bind() 112
getsockname() 113
m Contents ix
Socket Connection 113
connect () 113
l i s ten( ) 114
accept() 114
getpeername () 114
Socket Communication 115
send() 115
sendt o ( ) 115
recv() 116
recvfrom() 116
close() 117
shutdown() 117
Socket Control 118
getsockopt() 118
setsockopt() 118
Binary/String Conversion 119
inet_ntoa() 119
inet_addr() 119
htons(), htonl(), ntohs(), ntohl() 119
Host and Service Information 120
gethostname() 120
gethostbyname () 120
gethostbyaddr () 121
getservbyname () 121
getservbyport () 122
Bibliography 123
Index 125