FreeBSD polling issue,

[zirias@]

How does the CALL instruction work? What happens when you RET from that? What does any of this have to do with interrupts?

Well ... IRET does the same (plus other stuff), fetching a return address from some stack. Only that this stack will always reside in "kernel space", therefore being much harder to mess with than some application's stack. Really something to think about, we're all doomed

 

[Crivens]

This is all wimp programming. Have I told you about the power of the "come from" instruction?
And maybe the OP should read up on computer architecture. I get the feeling that he does not mean by polling what everybody understands.