Well, in terms of IRL roleplaying, I've had the good luck to be involved with good groups of people who play by a few rules.   The first one is: unless you're doing something really stupid (stupid, not crazy), the GM's I've had won't kill you.  Capture you, take your stuff, and force you to bust out of a dungeon?  Yes.  Kill you?  No.  Rule number two is: If a PC is going to be killed off, it's usually discussed with the GM first, and done for a legitimate reason (the player is moving away or something like that), and death is done only if there are no other options.  Final rule is: if the GM is trying to kill you, he will tell you, and is doing it for good reason.  The last rule's only come up at conventions, though - the GM was trying out new systems, and wanted to see how much he could throw at a party before it got to be too much.