Why can't I get these render command lines to work? All I get is 'command not found'. Previously I asked this question: Can files be queued for animation? The answers pointed me in the right direction, but I tried everything with no luck.

I thought there might be a problem with some old 'developer' software I had installed, so I decided to do a clean install of the operating system (OS X), but still no luck.

Are there any other Mac users out there who can give me some clues as to what's going on here? Any help would be greatly appreciated.