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Hour 4. Callbacks > Synchronous and Asynchronous Code - Pg. 50

50 HOUR 4: Callbacks TRY IT YOURSELF If you have downloaded the code examples for this book, this code is hour04/example04. The following steps demonstrate callbacks: 1. Copy the code in Listing 4.1 into a file on your system called app.js. 2. Create two files, called file1.txt and file2.txt, and add some text to them. You might want to use some Latin text from http://www.lipsum.com/. 3. Run the script: node app.js 4. You should see that the callbacks from reading the file are fired first, then the two http. get operations. 5. Run the script a few more times. Think about how these events are happening asynchro- nously and how callbacks are used to do other things when operations have finished. Synchronous and Asynchronous Code