pthread_cancel(3)					     Library Functions Manual						 pthread_cancel(3)

NAME

       pthread_cancel - Allows a thread to request a thread to terminate execution.

LIBRARY

       DECthreads POSIX 1003.1c Library (libpthread.so)

SYNOPSIS

       #include <pthread.h>

       int pthread_cancel(
			pthread_t   thread);

STANDARDS

       Interfaces documented on this reference page conform to industry standards as follows:

       IEEE Std 1003.1c-1995, POSIX System Application Program Interface

PARAMETERS

       Thread that receives a cancelation request.

DESCRIPTION

       This  routine  sends  a cancelation request to the specified target thread.  A cancelation request is a mechanism by which a calling thread
       requests the target thread to terminate as quickly as possible.	Issuing a cancelation request does not guarantee that  the  target  thread
       will receive or handle the request.

       When the cancelation request is acted on, all active cleanup handler routines for the target thread are called.	When the last cleanup han-
       dler returns, the thread-specific data destructor routines are called for each thread-specific data key with a destructor and for which the
       target thread has a non-NULL value.  Finally, the target thread is terminated.

       Note  that cancelation of the target thread runs asynchronously with respect to the calling thread's returning from pthread_cancel(3).  The
       target thread's cancelability state and type determine when or if the cancelation takes place, as follows: The target thread can delay can-
       celation  during  critical  operations  by setting its cancelability state to PTHREAD_CANCEL_DISABLE.  Because of communication delays, the
       calling thread can only rely on the fact that a cancelation request will eventually become pending in the target thread (provided that  the
       target  thread  does  not  terminate beforehand).  The calling thread has no guarantee that a pending cancelation request will be delivered
       because delivery is controlled by the target thread.

       When a cancelation request is delivered to a thread, termination processing is similar to that for pthread_exit(3).  For  more  information
       about thread termination, see the discussion of thread termination in pthread_create(3).

       This  routine  is  preferred  in  implementing  an Ada abort statement and any other language- or software-defined construct for requesting
       thread cancelation.

       The results of this routine are unpredictable, if the value specified in thread refers to a thread that does not currently exist.

RETURN VALUES

       If an error condition occurs, this routine returns an integer value indicating the type of error.  Possible return values are  as  follows:
       Successful completion.  The specified thread is invalid.  The thread argument does not specify an existing thread.

ERRORS

       None

RELATED INFORMATION

       Functions: pthread_cleanup_pop(3), pthread_cleanup_push(3), pthread_create(3), pthread_exit(3), pthread_join(3), pthread_setcancelstate(3),
       pthread_setcanceltype(3), pthread_testcancel(3)

       Manuals: Guide to DECthreads and Programmer's Guide

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																 pthread_cancel(3)