1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
#
# The Dining Philosophers - thread example
#
require "thread"
srand
#srand
N=9 # number of philosophers
$forks = []
for i in 0..N-1
$forks[i] = Mutex.new
end
$state = "-o"*N
def wait
sleep rand(20)/10.0
end
def think(n)
wait
end
def eat(n)
wait
end
def philosopher(n)
while true
think n
$forks[n].lock
if not $forks[(n+1)%N].try_lock
$forks[n].unlock # avoid deadlock
next
end
$state[n*2] = ?|;
$state[(n+1)%N*2] = ?|;
$state[n*2+1] = ?*;
print $state, "\n"
eat(n)
$state[n*2] = ?-;
$state[(n+1)%N*2] = ?-;
$state[n*2+1] = ?o;
print $state, "\n"
$forks[n].unlock
$forks[(n+1)%N].unlock
end
end
for n in 0..N-1
Thread.start(n){|i| philosopher(i)}
sleep 0.1
end
sleep
|
