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Deadlock condition



Conditions for a Deadlock To Occur

No Preemption: no resource can be forcibly removed from a process holding it.If a process that is holding some resources requests another resource that cannot be immediately allocated to it, then all resources currently being held are released implicitly. Then the preempted resources are added to the list of resources for which the process is waiting. 


Circular Wait: a closed chain of processes exists, such that each process holds at least one resource needed by the next process in the chain. Circular wait condition applies, since each vehicle is waiting on the next vehicle to move. That is, each vehicle in the traffic is waiting for a section of street held by the next vehicle in the traffic.


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