Linux is one of the most popular operating systems in existence today, partly because it's a free, open-source system that allows users to have greater control, and partly because some people prefer to avoid Microsoft. Regardless of the reasons, its undeniably a favorite system of developers and it provides a wealth of commands that permit you to interface with the operating system.
Most Linux commands are very similar to those of a UNIX operating system, so if you know UNIX, you won't have any trouble with Linux. Below are three examples of how to schedule HTTP requests in a Linux environment.
This CRON job uses the 'wget' command to schedule a recurring request, with no file output at all
The wildcards preceding the wget command make the request a recurring one
-o directs all output to standard output (STDOUT)
>/dev/null causes standard output to be nulled out and go nowhere
2>&1 causes any STDERR output to also be nulled out and go nowhere
As an alternative to using output redirection, you could specify 'wget -q0' which simply tells Linux to make all output 'quiet', i.e. to turn it off
This job can be executed in an Ubuntu environment. Ubuntu is one of the many operating systems which include the Linux core, but which make use of their own interfaces. Along with 'wget, 'curl' is one of the two main commands used for sending HTTP requests. The big difference between the two is that 'curl' is better suited to sending HTTP requests and receiving back results, and will not work when you want to download a page along with its internal links - only 'wget' can do that.
to use a different HTTP method, substitute 'curl -X POST' for 'curl'
to save output to a file, substitute 'wget' for 'curl'
This job will run a CRON job a specified number of times, using the Apache Bench tool. Originally designed to do simple load testing on Apache servers, Apache Bench is open-source and can be used for a variety of operating system functions.
ab -n 500 -c 20 http://www.example.com/
The 'ab' parameters ('ab' invokes the Apache Bench tool):
-n indicates the total number of requests, in this case 500
-c indicates how many times you want to repeat the request, in this case 20
As you can see, scheduling HTTP requests in Linux is a fairly easy task that doesn't call for a lot of programming or script-writing. A familiarity with curl, get, and wget will be sufficient in most cases to accomplish such tasks, along with some knowledge of the useful parameters which can be used with each. To find out about what all those possible parameters are, and how they're used, do a 'man' command (short for manual) on the command line to have that information displayed. For instance 'man wget' will provide system documentation about the wget command.