shutdown procedure for OTP/supervisor process

[Dustin Sallings]

	What's the right way for having a supervisor managed process register 
for a shutdown procedure?  An easy way I can think of is via a linked 
process that has trap_exit set and a receive that waits for the event.  
Just seems like there might be a more formal way.

	Specifically, I've got a crash in something that has a multicast 
socket bound and I want to leave the close the port and leave the 
group.

--
SPY                      My girlfriend asked me which one I like better.
pub  1024/3CAE01D5 1994/11/03 Dustin Sallings <dustin@REDACTED>
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