Software Solution 2 (incomplete)

• Only two processes.

• Local process is i, other is j.

• Mutual exclusion - good.

• Progress - bad. If both executed the second line before any of them entering the while statement, we have a problem.

• Bounded time - irrelevant.

Shared flag: array [0..1] of boolean=[false, false];

Repeat

flag[ i ] := true;

while flag[ j ] do no-op;

critical section

flag[ i ] := false;

remainder section

Forever

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