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Test and Set Lock

Consider the ...

Question

Consider the following code of processes 'i' & 'j'
int lock = 0, turn;
void process (int i)
{
int j = NOT(i);
while (1)
{
turn = i;
while (lock ! = 0 && turn = = i);
lock = 1;
<CS>
lock = 0;
}
Which of the following is true?

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Solution

It fails to guarantee mutual exclusion

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