6.5. Navigating a filesystem

Sources with filesystems that support enumeration (EXT2, ISO9660 etc.) can be browsed and navigated. A filesystem arranges information as files within directories. The file navigation commands (see File Navigation) can be used to change the present working directory (PWD) and enumerate (list) the contents of directories.

A filesystem is presented as a hierarchical tree of directories which contain files and more directories. ABLE presents directories in the UNIX® manner and includes the . and .. directories which represent the current directory and the parent directory respectively. Any file or directory name prefixed by a . is considered “hidden” and will not be listed with the ls command unless the -a option is used.

ABLE starts with the PWD set to the root directory /. As already seen in Example 6.1, “Using the ls command to list available sources.” this directory contains all available sources, by default only the alias sources are listed, the raw sources being “hidden”.

The cd command is used to change the PWD. The ls command with no parameters lists the available files in the PWD.

Once a file is located the file manipulation commands can be used (see File manipulation commands) to examine or verify the file. The file command is especially useful for determining if ABLE can identify a file as an operating system image.