Mac OS X Snow Leopard: The Missing Manual (Missing Manuals)

16.7. Double-Clickable Unix Tools

Most people are used to thinking of Unix applications as programs you run from within Terminal. Many, though, appear in the Finder as regular old icons ”and in Panther and Tiger, you can open them by double-clicking, just as you would a traditional Mac OS X program. This trick isn't very useful for commands that require flags. But for some, like cal , clicking provides a quick way to run the program, especially if you keep it in your Dock.

To double-click a Unix program, though, you first have to find it ”and that may not be easy. Mac OS X's Unix directory structure is labyrinthine indeed.

But why not ask Terminal where the program is? You can do exactly that using the which command: which cal , for example. Terminal responds with /usr/bin/cal , telling you that cal resides in the /usr/bin directory.

To get there, use the open command in Terminal, like this: open/usr/bin . A window opens in the Finder; inside, you'll find the cal icon. Drag the icon to the right side of the Dock.

From now on, when you click that Dock icon, a new Terminal window opens, automatically displaying this month's calendar. You've shaved several precious seconds off the time it would have taken you to open iCal.