Beej's Guide to Network Programming

Using Internet Sockets

Brian "Beej Jorgensen" Hall
beej@beej.us

Version 2.4.1
June 25, 2007

Copyright © 2007 Brian "Beej Jorgensen" Hall


Contents


1. Intro
1.1. Audience
1.2. Platform and Compiler
1.3. Official Homepage
1.4. Note for Solaris/SunOS Programmers
1.5. Note for Windows Programmers
1.6. Email Policy
1.7. Mirroring
1.8. Note for Translators
1.9. Copyright and Distribution

2. What is a socket?
2.1. Two Types of Internet Sockets
2.2. Low level Nonsense and Network Theory

3. structs and Data Handling
3.1. Convert the Natives!
3.2. IP Addresses and How to Deal With Them

4. System Calls or Bust
4.1. socket()—Get the File Descriptor!
4.2. bind()—What port am I on?
4.3. connect()—Hey, you!
4.4. listen()—Will somebody please call me?
4.5. accept()—"Thank you for calling port 3490."
4.6. send() and recv()—Talk to me, baby!
4.7. sendto() and recvfrom()—Talk to me, DGRAM-style
4.8. close() and shutdown()—Get outta my face!
4.9. getpeername()—Who are you?
4.10. gethostname()—Who am I?
4.11. DNS—You say "whitehouse.gov", I say "63.161.169.137"

5. Client-Server Background
5.1. A Simple Stream Server
5.2. A Simple Stream Client
5.3. Datagram Sockets

6. Slightly Advanced Techniques
6.1. Blocking
6.2. select()—Synchronous I/O Multiplexing
6.3. Handling Partial send()s
6.4. Serialization—How to Pack Data
6.5. Son of Data Encapsulation
6.6. Broadcast Packets—Hello, World!

7. Common Questions

8. Man Pages
8.1. accept()
8.2. bind()
8.3. connect()
8.4. close()
8.5. gethostname()
8.6. gethostbyname(), gethostbyaddr()
8.7. getpeername()
8.8. errno
8.9. fcntl()
8.10. htons(), htonl(), ntohs(), ntohl()
8.11. inet_ntoa(), inet_aton()
8.12. listen()
8.13. perror(), strerror()
8.14. poll()
8.15. recv(), recvfrom()
8.16. select()
8.17. setsockopt(), getsockopt()
8.18. send(), sendto()
8.19. shutdown()
8.20. socket()
8.21. struct sockaddr_in, struct in_addr

9. More References
9.1. Books
9.2. Web References
9.3. RFCs

Index