Sorting Options

The sorting options are probably what distinguishes tree most from ls. The default is alphabetical order, but if you suspect a file or directory might be at the bottom of the alphabet, -r will list results in reverse alphabetical order instead (Figure 5). Similarly, --dirfirst can save you time by listing all the directories first if you are reasonably sure that what you are looking for is a directory.

Figure 5: The -r option lists results in reverse alphabetical order.

Other handy sorting options include last modification time (-t) and last status change (-c). However, the option most likely to interest developers is version (-v), which can help locate a particular generation of a file.

The Next Generation

The ls command existed in the first version of Unix [3]. It remains a core command, and tree is not immediately obvious as an enhanced, next generation replacement.

However, the minor advantages of tree start to add up. In particular, its ability to exclude large portions of the directory structure and its extra sorting abilities make it slightly quicker for finding most files and directories.

Additionally, its visual representation of drives should not be underestimated. By desktop standards, tree's representation of files and directories is primitive. Yet the tree is how people are taught to think about files and directories, and to see your mental representation on the screen only makes interacting with tree easier.

The advantage of tree is not great in any single case. However, the more you do file management at the command prompt, the more tree's advantages mount. Take the time to learn it, and you might decide that ls has had its day.

For more information, check out the extensive examples of how to use tree from Barracuda Firewall  [4].