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This code instead uses the pthread_cancel() to terminate the thread. The thread continues to run until it reaches a cancellation point. See the second referenced article [MKS] for a list of functions that are cancellation points. If the cancellation type is set to asynchronous, the thread is terminated immediately. However, POSIX only requires the pthread_cancel(), pthread_setcancelstate(), and pthread_setcanceltype() functions to be async-cancel safe. An application that calls other POSIX functions with asynchronous cancellation enabled is non-conforming.
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