PHP Shell Scripting for Linux/Unix Administrators

This section is a brief overview of PHP, and some system related aspects of PHP, that are helpful to know.

PHP is an interpreted language, here are some things to understand about PHP, as opposed to or like PERL.

The unique advantage of PHP, is that you can easily run it over the command line, or through mod_php in apache. Php is also adapt to database connections, with a modern library of current database support.

INI Files are the basis for global PHP configuration, here is where to find them on the system.

The most common values that need to be changed in a PHP INI file are listed in this lesson.

In this section we look at a working script, which compares the contents of two files, they are actually database table dumps, and the script goes and determines which tables are missing from the other file.

First we start with a script, that is written, and explore what it does.

Looking at the files we are searching for, we begin to further understand what the script is doing, and learn about refined parsing methods.

Looking further still we examine and explore the rest of the file, and make deductions about what we might want to change later on.

Now that we understand a bit about the script, we start to modify it, by employing a function to reduce and reuse code.

Now we go and look at some web resources, a good place to find some help.

Now we are going to learn PHP, by building a script.

Let's look at a design template.

Lets turn some code into a function.

This is my most valuable too, the syscall function. Let's learn how it works, and what it allows us to do.

Let's replace the system call with syscall, and measure the result.

Look at ways to implement flexible array processing.

Add a search variable, so that you can easily change what you are searching for.

Instead of one search term, turn that into a passable array.

We look at another way to loop through an array.

Utilize command line arguments to add flexibility to your program.

An introduction into converting a bash script into a PHP script.

Lets take a look at the bash script we are going to convert.

Convert commands to variables.

Use this PHP feature to debug arrays.

Add the Convert FD functionality.

We adjust PHP to match the output formatting, so we get the same functionality as we did with the bash script.

Let's talk about a real-world use case, and discuss how to solve the problem.

Here is a script, which makes a config file, that the main script will use.

To view the config file, we write a short script to display its contents.

Now we take an in-depth look at the main script, and see how to access the data in the config file.

Here is how to configure PHP to send mail. This library works great!

Here is where I got the mail library from, download yourself a copy as well.

Here is a look at the contents of the zip file, so you can examine what the output files look like.

It is always good to use a debug file, this catches all the standard output from the cron job.