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The last thing I'm going to show you is how you can capture the state of your application without terminating the script. This is done by using the error log function. The error log function allows you to capture the state of your browser through the use of a string and send it to a log file where you can view it later on. This is done by using the error log function, which takes three parameters. First, it takes some sort of text, a message that you can catenate or put together. Then it takes one of four integers. The meaning of the different integers are documented in the PHP manual online. In this case we're going to use three, which is the most common. The integer three means go ahead and just append the current message onto the existing file. The last one's going to be the path to the file and the name of the file. Now, when you specify the name and the path of your file, you need to be aware that the web server is the one that's executing the script so it needs to have write permissions to that file and director. Which directory and which text file you use depends upon which web server and which operating system that web server is running on. In this instance, we're using Mac OS 10 and the Apache web server and a very good place to create your log file in Mac OS 10 is inside the temp director. The temp directory is at forward slash tmp forward slash. When I go to that directory, you can see that I currently have an item there that's placed there by another application or by the operating system. And this is where I'm going to create my log file. I'm going to say error log, and the message is going to be text, and the path is going to be forward slash tmp and the name of the file is going to be error log.txt. Now, the web server will try to append my current message and if the error log doesn't exist, it will create it. Let's go ahead then and refresh this in the browser. And watch the temp directory. Here's my error log. When I open it up, you can see my message. So you can place inside of your error log function whatever kind of message is going to be helpful for you as the programmer and administrator to help debug your application or to monitor its status. Inside this message you could do something like create the current UNIX time stamp and concatenate that with a message and a new line return. Now go ahead and close our log and refresh this a few more times so that the browser has executed this script several times. And we'll open up our error log. In here we can see that we now have a Unix time stamp prepending our message and then a new line return so that the next error log entry is forced onto its own new line. So, as you can see, with a little bit of imagination you could create quite an extensive log file and you can use the error log function at any point during your application. So I could bump this line of code up to one of my loops and even put variables inside here that says X is equal to X, and I is equal to the variable I. And then again, refresh this in the browser and get a very verbose log file. So with the error log function, you can capture the status of your current PHP application and you can log your entries for administrative or debugging purposes. It's even nice to be able to create the error log function inside of your own custom function that maybe perhaps looks for a variable or a constant that you've defined to see if you want debugging turned on or turned off. That way you can go into a certain included file and set a constant or a variable to on or off dependent upon whether or not you want logging to occur during the running of your application or not. So here's how you can capture your current PHP application and how you can terminate your scripts and concludes this lesson.