Question

Is the block of code of an included file ‘grabbed’ when the calling script first starts or when the include statement is reached? Take for example:

// execute many lines of code
sleep(10);
// do file retrievals that takes many minutes
include('somefile.php');

If the original code is executed (commenced), is the code block of somefile.php put in memory at that instant or not until the include statement is reached?

Answer 1

When the include statement is executed/run.

PHP is executed line by line. So, when the process arrives at the include, it will do its magic.

For example:

//some code
//some more code
//even more
include('file.php');//now all of file.php's contents will sit here 
//(so the file will be included at this point)

See http://php.net/manual/en/function.include.php