Chapter 4: Advanced Sockets Functions

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Overview

In this chapter, we continue looking at the details of the Sockets API, in this case some advanced functions and some other functions whose usage is rare. This discussion, as in the prior chapter, is based on the Linux API. The prototypes and usage apply to other implementations as well. The Sockets functions that are discussed in this chapter are shown in Table 4.1. All code for this chapter can be found on the companion CD-ROM under /software/ch4.

Table 4.1: SOCKETS FUNCTIONS DISCUSSED IN CHAPTER 4

Function	Description
select	Provides event notification of socket events
getsockname	Returns the address of the local socket
getpeername	Returns the address of the remote socket
getsockopt	Returns the value of a socket option for a given socket
setsockopt	Manipulates a socket option for a given socket
shutdown	Closes a socket with more control
gethostname	Retrieves the name of the host on which this stack operates
sethostname	Sets the name of the host on which this stack operates
gethostbyaddr	Returns the FQDN for a given IP address
gethostbyname	Returns the IP address for a given FQDN
getservbyname	Returns the port number for a given service string
getservbyport	Returns the service string for a given port number

The following subsections illustrate the API calls, and discuss any special characteristics of their application and common problems that are associated in their use.

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