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Issue 3: 1.8 Exercise 2.
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Project Member Reported by sergeypr...@gmail.com, Aug 21, 2014
Exercise 2. For each of the following, state whether it is a safety or liveness property.

Identify the bad or good thing of interest.
1. Patrons are served in the order they arrive.
2. What goes up must come down.
3. If two or more processes are waiting to enter their critical sections, at least one
succeeds.
4. If an interrupt occurs, then a message is printed within one second.
5. If an interrupt occurs, then a message is printed.
6. The cost of living never decreases.
7. Two things are certain: death and taxes.
8. You can always tell a Harvard man.
Aug 21, 2014
Project Member #1 sergeypr...@gmail.com
Solution:
Liveness - smth eventually happens (что-то в конце концов произойдет)
safety - nothing bad happens (ничего плохого не случится)
(read from http://www.doc.ic.ac.uk/~jnm/book/firstbook/pdf/ch7.pdf)

1. Real things, it is liveness
2. it's liveness, not bad happens.
3. it's liveness, not bad happens at least one enter to critical section.
4,5 - not bad happens - message is printed.
6. it's safety property. The "bad" thing will never happen that the cost of living is decreases.
7. it is real situation, it is liveness.
8. you never tell a Harvard man (http://en.wikipedia.org/wiki/Harvard_Man) - it is safety.


Sep 4, 2014
Project Member #2 sh.ba...@gmail.com
well done! :)
Sep 4, 2014
Project Member #3 sh.ba...@gmail.com
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Status: Done

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