Tcl can communicate with applications and devices using a variety of protocols and talk to different types of hardware—embedded devices, routers, desktops, and servers.
We can use e-mail to communicate with users and/or applications. Tcl allows us to send and retrieve e-mails. It also offers mechanisms for parsing and building MIME messages that include support for attachments, inlined images, multiple document types, and different encoding systems.
We can use Tcl to transfer files over FTP and HTTP. We can use this to retrieve information, communicate with server part of our application, download updates, upload results as well as many other operations. We can also automate web-based operations using HTTP client.
In this chapter, we have learned how to:
- Send e-mails from Tcl
- Build e-mails containing HTML and plain text message, attachments, and inlined images
- Retrieve, parse, and process e-mail messages
- Get data over HTTP
- Read RSS feeds
- Upload and download files over FTP
The next chapter talks about some of additional network protocols and how they can be used from Tcl. It describes how to query for DNS information, and retrieve the current date and time from remote servers.