pthread_testcancel(3c) [opensolaris man page]

pthread_testcancel(3C)					   Standard C Library Functions 				    pthread_testcancel(3C)

NAME

       pthread_testcancel - create cancellation point in the calling thread

SYNOPSIS

       cc -mt [ flag... ] file... -lpthread [ library... ]
       #include <pthread.h>

       void pthread_testcancel(void);

DESCRIPTION

       The pthread_testcancel() function forces testing for cancellation. This is useful  when you need to execute code that runs for long periods
       without encountering cancellation points; such as a library routine that executes long-running computations  without  cancellation  points.
       This  type of code can block cancellation for unacceptable long periods of time.   One strategy for avoiding blocking cancellation for long
       periods, is to insert calls to pthread_testcancel() in the long-running computation code and to setup a cancellation handler in the library
       code, if required.

RETURN VALUES

       The pthread_testcancel() function returns void.

ERRORS

       The pthread_testcancel() function does not return errors.

EXAMPLES

       See  cancellation(5)  for  an example of using pthread_testcancel() to force testing for cancellation and a discussion of cancellation con-
       cepts.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       Intro(3), pthread_cleanup_pop(3C), pthread_cleanup_push(3C), pthread_exit(3C), pthread_join(3C),  pthread_setcancelstate(3C),  pthread_set-
       canceltype(3C), setjmp(3C), attributes(5), cancellation(5), condition(5), standards(5)

NOTES

       The pthread_testcancel() function has no effect if cancellation is disabled.

       Use  pthread_testcancel()  with pthread_setcanceltype() called with its canceltype set to PTHREAD_CANCEL_DEFERRED. The pthread_testcancel()
       function operation is undefined if pthread_setcanceltype() was called with its canceltype argument set to PTHREAD_CANCEL_ASYNCHRONOUS.

       It is possible to kill a thread when it is holding a resource, such as lock or allocated memory. If that thread has not setup  a  cancella-
       tion  cleanup  handler  to  release  the  held resource, the application is "cancel-unsafe".  See attributes(5) for a discussion of Cancel-
       Safety, Deferred-Cancel-Safety, and Asynchronous-Cancel-Safety.

SunOS 5.11							    23 Mar 2005 					    pthread_testcancel(3C)

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pthread_setcancelstate(3C)												pthread_setcancelstate(3C)

NAME

       pthread_setcancelstate - enable or disable cancellation

SYNOPSIS

       cc -mt [ flag... ] file... -lpthread [ library... ]
       #include <pthread.h>

       int pthread_setcancelstate(int state, int *oldstate);

       The pthread_setcancelstate() function atomically sets the calling thread's cancellation state to the specified state and if oldstate is not
       NULL, stores the previous cancellation state in oldstate.

       The state can be either of the following:

       PTHREAD_CANCEL_ENABLE   This is the default. When cancellation is deferred (deferred cancellation is also the default), cancellation occurs
			       when  the  target  thread  reaches a cancellation point and a cancel is pending. When cancellation is asynchronous,
			       receipt of a  pthread_cancel(3C) call causes immediate cancellation.

       PTHREAD_CANCEL_DISABLE  When cancellation is deferred, all cancellation requests to the target thread are held pending.	When  cancellation
			       is  asynchronous,  all  cancellation requests to the target thread are held pending; as soon as cancellation is re-
			       enabled, pending cancellations are executed immediately.

       See cancellation(5) for the definition of a cancellation point and a discussion of cancellation concepts. See pthread_setcanceltype(3C) for
       explanations of deferred and asynchronous cancellation.

       The  pthread_setcancelstate()  function is a cancellation point when it	is called with	PTHREAD_CANCEL_ENABLE and the cancellation type is
       PTHREAD_CANCEL_ASYNCHRONOUS.

       Upon successful completion, pthread_setcancelstate(), returns 0. Otherwise, an error number is returned to indicate the error.

       The pthread_setcancelstate() function will fail if:

       EINVAL	       The specified state is not PTHREAD_CANCEL_ENABLE or PTHREAD_CANCEL_DISABLE.

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

       pthread_cancel(3C),  pthread_cleanup_pop(3C),  pthread_cleanup_push(3C),  pthread_exit(3C),  pthread_join(3C),	pthread_setcanceltype(3C),
       pthread_testcancel(3C), setjmp(3C), attributes(5), cancellation(5), condition(5), standards(5)

								    23 Mar 2005 					pthread_setcancelstate(3C)

Linux and UNIX Man Pages

pthread_testcancel(3c) [opensolaris man page]

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