Macintosh Terminal Pocket Guide

Navigating the Filesystem

When you open a Finder window and work with its icons, that window represents a particular folder. Likewise, when you open a Terminal window, its shell is working “in” some directory. More technically, your shell has a current working directory (analogous to your open Finder window). When you run commands in that shell, they operate relative to the current working directory. Figure 1-7 illustrates this concept. If your shell is “in” the directory /Users/smith/stuff, and you run a command that refers to a file receipt.pdf, then the file is really /Users/smith/stuff/receipt.pdf.

Figure 1-7. A Finder window (left) and Terminal window (right) displaying the same folder, /Users/smith/stuff

If a path begins with a slash, such as /one/two/three, it’s called an absolute path. If not, it’s a relative path, because it’s relative to a shell’s current location in the filesystem. For instance, a relative path a/b/c, when referenced from the current directory /one/two/three, implies the absolute path /one/two/three/a/b/c. In general, if you refer to a relative file path in a shell, the path is relative to your current working directory.

Two special relative paths are . (a single period) and .. (two periods in a row). A single period refers to your current directory, and two periods means your parent directory, one level above. So if your current directory is /one/two/three ...