# Chapter 14. File System Usage for KDevelop Projects

As the last chapter covered the KDE File System Standard, this chapter deals with what you have to do to use the file system. A KDE project uses the file system at least for installation routines; therefore we will discuss setting installation properties for your project files. Your application may make use of files that are installed afterwards, where it is important to know how to get the relative pathname by the standard. This enables your application to work wherever the KDE file system may be and prevents hard-coding any file information.

# 14.1. Accessing Files during Runtime

After the installation of your project by end-users, your application may require file information during runtime. During the development process, you will experience at least one error which is caused when running your application within the KDevelop IDE and requiring the application manual by "Help"-"Contents" or pressing the F1 key. This will result in a message box, saying that the index.html file could not be found- if you haven't installed your application on your local KDE file system. Your application asks KDEHelp to open your index page with detecting the installation directory first through `KApplication`'s methods to access the file system, therefore, we will have a look at what `KApplication` offers and make some example usage. Also other classes of `KDE-Core` make use of the KDE File System like `KIconLoader` and `KLocale`, which will be reviewed afterwards.