Apress - Smart Home Automation with Linux (2010)- P45:Linux users can now control their homes remotely! Are you a Linux user who has ever wanted to turn on the lights in your house, or open and close the curtains, while away on holiday? Want to be able to play the same music in every room, controlled from your laptop or mobile phone? Do you want to do these things without an expensive off-the-shelf kit | CHAPTER 6 DATA SOURCES if stristr rss- items i title nasa system sendsms myphone rss- items i description This can be particularly useful for receiving up-to-minute sports results lottery numbers or voting information from the glut of reality TV shows still doing the rounds on TV stations the world over. Even if it requires a little intelligent pruning to reduce the pertinent information into 140 octets in the United States or 160 characters in Europe RSA and Oceania which is the maximum length of a single unconcatenated text message it will be generally cheaper than signing up for the paid-for services that provide the same results. Retrieving Data Pull This encompasses any data that is purposefully requested when it is needed. One typical example is the weather or financial information that you might present at the end of the news bulletin. In these cases although the information can be kept up-to-date in real time by simulating a push technology few people need this level of granularity once a day is enough. For this example you will use the data retrieved from an online API to produce your own currency reports. This can be later extended to generate currency conversion tables to aid your holiday financing. The data involved in exchange rates is fairly minimal and consists of a list of currencies and the ratio of conversion between each of them. One good API for this is at . It provides a SOAP-based API that offers up-to-date reports of various currencies. Which specific currencies can vary over time so has thoughtfully provided an enumeration function also. If you re using PHP and PHP-SOAP then all the packing and unpacking of the XPI data is done automatically for you so that the initialization of the client and the code to query the currency list is simply as follows client new SoapClient http currencies client- getCurrencies The getCurrencies method is detailed by the Web Services Description Language WSDL . .
