Directories

Files are grouped in a directory, which is a special kind of file consisting of the names of a set of files and other information about them. Usually, the files in a directory are related to each other in some way. The files listed can be thought of as being contained in that directory (although their actual locations in physical storage are managed by the operating system).

A directory can include a file that is itself a directory (sometimes referred to as a subdirectory) and so on, through a number of levels in a hierarchical arrangement. For example, in Figure 1, the slash (/) symbol at the top represents the root directory, which all other directories are descended from. There are ten directories branching from the root. Each of these directories, in turn, has its own system of subdirectories and files. For example, localedef is a subdirectory in the directory /usr/lib/nls.

When you first enter the z/OS shell, you are automatically placed in your home directory, which is defined when your user ID is defined.