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Open Source Technologies

Notes
echo $ file. “\n”
}

}
When you view the output of this script in your browser, you should see a list of the files
in the named directory. How did this happen? Well, the Directory Iteratr class provieds a
pre-built interface to iterating over the contents of a directory; once instantiated with the
location of the target directory, it can then be processed as though it were a standard PHP
array, with each element representing a file in the directory. Note the use of the is Dot 90
method to filter out the “.” and “.” directories, respectively.

Processing a Nested Directory Tree
Recursively processing a nested directory tree is almost as simple. In this case, the Directory
Iterator needs to check each object it encounters within the first-level directory, determine
whether it is a file or directory, and, if a directory, drill one level deeper to examine the
next level of contents. this sounds fairly complex, and in the past could easily add up to
15-plus lines of code.
With_PHP5, though, all you need are two iterators: the Recursive Directory Iterator and
the Recursivelterator Iterator, which together incorporate all the above functionality.
Take a look at.
Listing A

Questions

1. How Scan directories and PHP interrelated?
2. What is processing a nested directory tree?

11.8 Summary

• Validating the file helps to limit the file size.

• Fopen( ) is the command that opens the file for reading or writing. It accepts a file name
and one of six arguments =r,rt, wt, a, at for unity of files.

• Deleting a file using PHP is done by using the unlink function.

• If you want to append to a file, i.e. add on to the existing data, them you need to open
the file in append mode.

11.9 Keywords

CHMOD: It is a Unix command that lets you tell the system how much (or little) access it should
permit to a file.

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