Capture an event (such as when a user changes an edit field or presses a button).
Total: <input type="text" id="total" />
document.getElementById('total').value = <some value>;
Listing 1. index.html
Listing 2. getShipping.php
<?php echo "$5.00"; ?>
This first example avoids XML entirely. The following line of code grabs the result as plain text:
results = http.responseText;
Keep in mind that the above example takes as many shortcuts as possible to keep it simple. There is no error checking or error handling whatsoever. There aren't even any HTML tag names, only ids. For example, it would be more common to create an input field that reads <input type="text" name="totalshipping" id="totalshipping" />. You probably wouldn't place the shipping cost in a field that a person could edit (although your form could re-validate the shipping when the person clicked “purchase” to correct any user changes). In addition, the example doesn't actually calculate a shipping cost. The URL in the above code points to a simple PHP script that returns the text value “$5.00” (Listing 2). A real application would take the zip code and use it to calculate the shipping cost and return that value. In short, the example cuts every possible corner to isolate how Ajax works rather than how one should code an Ajax application.
Practical Task Scheduling Deployment
July 20, 2016 12:00 pm CDT
One of the best things about the UNIX environment (aside from being stable and efficient) is the vast array of software tools available to help you do your job. Traditionally, a UNIX tool does only one thing, but does that one thing very well. For example, grep is very easy to use and can search vast amounts of data quickly. The find tool can find a particular file or files based on all kinds of criteria. It's pretty easy to string these tools together to build even more powerful tools, such as a tool that finds all of the .log files in the /home directory and searches each one for a particular entry. This erector-set mentality allows UNIX system administrators to seem to always have the right tool for the job.
Cron traditionally has been considered another such a tool for job scheduling, but is it enough? This webinar considers that very question. The first part builds on a previous Geek Guide, Beyond Cron, and briefly describes how to know when it might be time to consider upgrading your job scheduling infrastructure. The second part presents an actual planning and implementation framework.
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With all the industry talk about the benefits of Linux on Power and all the performance advantages offered by its open architecture, you may be considering a move in that direction. If you are thinking about analytics, big data and cloud computing, you would be right to evaluate Power. The idea of using commodity x86 hardware and replacing it every three years is an outdated cost model. It doesn’t consider the total cost of ownership, and it doesn’t consider the advantage of real processing power, high-availability and multithreading like a demon.
This ebook takes a look at some of the practical applications of the Linux on Power platform and ways you might bring all the performance power of this open architecture to bear for your organization. There are no smoke and mirrors here—just hard, cold, empirical evidence provided by independent sources. I also consider some innovative ways Linux on Power will be used in the future.Get the Guide