Broke a brake pad retaining clip - how critical?

Saab 900S. Replaced the front ball joints to try to resolve a noise (it didn't), and when I got home from the test drive I noticed the right rear brake was smoking. Great. Pads are pretty worn, so it must have been happening for a while. Anyway, in pulling it apart to try to free it up, the brake pad retaining clip on the outside of the caliper snapped off, leaving a small bit stuck in the caliper, which of course won't come out. How critical is the clip? Am I taking my life in my hands if I leave it broken for a while? Or is it more of an anti-rattle/anti-squeal sort of a thing?

Pix please

Not my photo, but you can see the clip well in this shot. It broke at the bottom hole.

The test drive indicates that the brake is now free at least, and seems to be functioning normally in spite of the broken clip.

Looks like a rattle clip to me. I would look closely to make sure it doesnt pull the pad back out somehow. If not I would run it until I could replace it but I wouldnt drag my feet doing that either.

The picture doesn't answer enough. If there are slider bolts retaining the caliper to the bracket you are OK. If that spring is what holds the caliper to the bracket, as it looks from the photo, you absolutely need it.

Just an FYI. I think those clips come with sets of new pads. If you don't need a pad swap now you can stash them away and just use the clip.  

Clearly I was too aggravated to write a proper description yesterday, so let me see if I can do a better job.

The caliper is a conventional single piston sliding caliper, with two slider bolts attaching the carrier section to the bracket. The clip applies tension to the carrier, pulling the outer edge toward the bracket, but the primary means of securing the two together is the slider bolts. There is a provision for the hand brake via a lever in the back; this was not the issue (I replaced a frozen cable last fall, and the lever moves freely).

The sliders were rather firmly encrusted with dirt but not rusted. I cleaned them thoroughly with emery cloth and scotchbrite pads, and applied caliper grease to the sliders and the channels where the pad ears ride. A short test drive with plenty of braking shows that the caliper seems to be free right now. I will need to throw new pads in there soon, but the problem is the broken stub of the clip is embedded in the caliper. I will have to try to drill it out before I can replace the clip. If that doesn't work I'll have to track down a caliper.

Ever see the movie Tommy Boy?

The new guy is going to be over in the corner puking his brains out all because you wanted to save .34 on a pad retaining clip.

(Not really, I just wanted to put the fear in there. In all honesty you want that affirmation that it'll be okay because you want to button up the car and get the job done. But if you do that without putting a new clip in, you are going to severtly question the quality of the job and wish and feel that you should have gotten a new clip to have done the job right. Unless you absolutely need the vehicle to be operational within the next two days, get a new clip to put in, you'll feel better about it in the coming weeks). 

In reply to captdownshift (Forum Supporter) :

No, I really just want to better understand the function of the clip. I'm way too OCD to just leave it, but time is limited at the moment and I do need the car to move some stuff this weekend.

I would not drive without it because I don't know how much the caliper can move toward the wheel without it. It provides tension to pull the caliper and bracket together. 

Common part to lots of calipers from that age.  No problem at all to drive without it, other than the potential for a rattle.  Because it's an anti rattle spring...

I'd try to find one to put on later.