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PTHREAD_CANCEL(3)        BSD Library Functions Manual        PTHREAD_CANCEL(3)

     pthread_cancel -- cancel execution of a thread

     #include <pthread.h>

     pthread_cancel(pthread_t thread);

     The pthread_cancel() function requests that thread be canceled.  The target thread's cancelability
     state and type determines when the cancellation takes effect.  When the cancellation is acted on, the
     cancellation cleanup handlers for thread are called.  When the last cancellation cleanup handler
     returns, the thread-specific data destructor functions will be called for thread.  When the last
     destructor function returns, thread will be terminated.

     The cancellation processing in the target thread runs asynchronously with respect to the calling thread
     returning from pthread_cancel().

     A status of PTHREAD_CANCELED is made available to any threads joining with the target.  The symbolic
     constant PTHREAD_CANCELED expands to a constant expression of type (void *), whose value matches no
     pointer to an object in memory nor the value NULL.

     If successful,  the pthread_cancel() functions will return zero.  Otherwise an error number will be
     returned to indicate the error.

     pthread_cancel() will fail if:

     [ESRCH]            No thread could be found corresponding to that specified by the given thread ID.

     pthread_cleanup_pop(3), pthread_cleanup_push(3), pthread_exit(3), pthread_join(3),
     pthread_setcancelstate(3), pthread_setcanceltype(3), pthread_testcancel(3)

     pthread_cancel() conforms to ISO/IEC 9945-1:1996 (``POSIX.1'').

     This man page was written by David Leonard <> for the OpenBSD implementation of

BSD                            January 17, 1999                            BSD

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