Palm Programming: The Developer's Guide

TCP/IP

In this section, we show you how to use TCP/IP on a Palm device. To accomplish this, we discuss the API for networking on a Palm device, we give you some programming tips for implementing TCP/IP, and last we create a small sample application that sends email to a Simple Mail Transfer Protocol (SMTP) server.

Network API

The Palm SDK (Version 2.0 or later) contains a net library that provides network services, like TCP/IP, to applications. With this library, an application on the Palm device can connect to any other machine on a network using standard TCP/IP protocols. The API for this library is a socket interface, modeled very closely on the Berkeley Sockets API.

Note

Sockets are a communication mechanism. Information is sent into a socket on one machine and comes out of a socket on a remote machine (and vice versa). With a connection-oriented socket interface, you can establish the connection between the two machines prior to sending data. The connection stay opens whether or not data is sent. A good example of this is TCP. Sockets also allow a connectionless mode for sending datagrams. These can be sent to an address without any prior connection using a protocol like User Datagram Protocol (UDP).

For a brief introduction to Berkeley Sockets and socket programming, see http://www.ibrado.com/sock-faq/. For a more detailed discussion, see Unix Network Programming, by W. Richard Stevens (Prentice Hall; ISBN: 0-13-949876-1).

The similarity between the Berkeley Sockets API and the ...