Oh my god. If you followed the link, you surely noticd the 170ish lines in the example that shows you how to make use of command-line arguments from JavaScript. I totally forgot how nasty it is to often to simple things in XUL/XPCOM-land.

In my adventures of searching for telling teaching a small xulrunner application I'm working on to use the commandline, I found Crowbar, a project out of MIT that's pretty neat.

Basically I wanted the power of my xpathtool but twist it with some help from jQuery. A command-line jquery tool would let you do some pretty neat things with web scraping. Crowbar can already do the page fetching, but I want to do more. And no, by 'command-line jquery tool' I certainly do not mean this command line jquery documentation tool.

My frustration with XPCOM's burden-the-programmer design has me at the end of my patience for tonight. Basically I suck at XPCOM in JavaScript. I'll keep at it though, maybe something useful will come out. come out of it.

Update: Neat! While surfing through Crowbar's code for how they handle commandline arguments, I found this beauty:

/*
 * Process a series of command line arguments and modify default settings
 */
function processCommandLineArgs() {
  var nsCommandLine = window.arguments[0];
  nsCommandLine = nsCommandLine.QueryInterface(Components.interfaces.nsICommandLine);
  port = getCommandLineArg(nsCommandLine, 'port', port);
}

So, I try this out myself:

<window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
        onload="alert(window.arguments[0].QueryInterface(Components.interfaces.nsICommandLine).getArgument(0))" />

And run xulrunner:

% xulrunner application.ini happypants

The result is this: