Launch an app on OS X with command line

As was mentioned in the question here, the open command in 10.6 now has an args flag, so you can call:

open -n ./AppName.app --args -AppCommandLineArg

In OS X 10.6, the open command was enhanced to allow passing of arguments to the application:

open ./AppName.app --args -AppCommandLineArg

But for older versions of Mac OS X, and because app bundles aren't designed to be passed command line arguments, the conventional mechanism is to use Apple Events for files like here for Cocoa apps or here for Carbon apps. You could also probably do something kludgey by passing parameters in using environment variables.

An application bundle (a .app file) is actually a bunch of directories. Instead of using open and the .app name, you can actually move in to it and start the actual binary. For instance:

$ cd /Applications/LittleSnapper.app/
$ ls
Contents
$ cd Contents/MacOS/
$ ./LittleSnapper

That is the actual binary that might accept arguments (or not, in LittleSnapper's case).