Chapter 6: Process Synchronization - Csl Mtu

Algorithm III: Progress 3/4
flag[i] = TRUE;
turn = j;
while (flag[j] && turn == j);
process P i
If P i is waiting to enter, it must be executing its
while loop.
Suppose P j is not in its critical section:
If P j is not interested in entering, flag[j] was
set to FALSE when P j exits. Thus, P i may enter.
If P j wishes to enter and sets flag[j] to TRUE,
it will set turn to i and P i may enter.
In both cases, processes that are not waiting do not
block the waiting processes from entering.
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