Hi all, I'm trying to create a time lapse of a lego build using 'imagesnap' and 'LAUNCHD' on the mac, but I can't get my script to output a timestamped image or random filenames. It just spits out files named "$RANDOM.jpg" and replaces itself every time. It worked in CRON, but I need the interval control I can get in launchd. Help, please? Here's the script I'm using now:

(Replace all [ with <>)

[plist]

[dict]

	[key]Disabled[/key]

	[false]

	[key]KeepAlive[/key]

	[true]

	[key]Label[/key]

	[string]syscheck[/string]

	[key]ProgramArguments[/key]

	[array]

		[string]/usr/share/imagesnap[/string]

		[string]-t *.jpg[/string]

		[string]mv[/string]

		[string]/Users/Print/$RANDOM.jpg[/string]

	[/array]

	[key]StartInterval[/key]

	[integer]15[/integer]

[/true][/false][/dict]

[/plist]"

Before, when I used CRON for snaps every minute, I did this:
"* * * * * /usr/share/imagesnap -t *jpg mv /Users/Print/$RANDOM.jpg"

... and it would output random filenames.

What am I doing wrong?