Just in case you are a complete noob, let me explain one of the hottest social networking tools, a micro-blogging service called Twitter. Twitter allows you to post messages of up to 140 characters (from your browser or a variety of applications) that can be seen either by the whole Twitter world or by select Twitter users. You can follow what everyone is posting or just follow your Twitter friends. (On Twitter I am "quistuipater".)

So, first up this week is a service that all Twitterholics would love if it actually worked properly: istwitterdown.com. The home page of istwitterdown reads “Yes” or “No” depending on the status of Twitter.com. Sounds cool, but all it actually seems to be telling you is whether the server is responding to pings, which is something that is quite different from whether Twitter is actually working properly, which, at the time of writing, it isn’t. Again. Actually, that should be yet again. Come on Twitter, I know it seems like rocket science, but really. . . .

At the end of this discussion we’ll come back to how istwitterdown should work. . . . 

Anyway, next up, a command line Twitter client. In a corporate context this is something that you might want to use to broadcast a “tweet” (that’s what Twitter messages are called) for events such as status updates for a service or device.

The Twitter REST-based (Representational State Transfer) API is relatively simple, and to post a tweet all you need to perform is a straightforward HTTP POST request. (Oh great, now Twitter is going up and down like a yo-yo.)

An easy way to post to tweet from a command line is to use cURL, a free open source tool that lets you use a URL format to perform data transfers.

cURL is dauntingly overblessed with features and can handle all of the major protocols, including HTTP, HTTPS, FTP, FTPS and even LDAP and Telnet. Better still, cURL is available for a large number of operating systems, including AIX, BeOS, DOS, various flavors of BSD, a huge number of Linux distros, OS X, NetWare (our younger readers may have heard of this), Solaris and Windows (both 32- and 64-bit versions).

To post to Twitter you have to have an account because the API requires you to authenticate. So using cURL in a command or terminal window, you enter a command line as follows (this command should be on a single line and the variables are underlined):