pthread_setcanceltype(3)pthread_setcanceltype(3)NAMEpthread_setcanceltype - Sets the current thread's cancelability type
int *oldtype );
DECthreads POSIX 1003.1c Library (libpthread.so)
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
IEEE Std 1003.1c-1995, POSIX System Application Program Interface
The cancelability type to set for the calling thread. The following are
valid values: PTHREAD_CANCEL_DEFERRED PTHREAD_CANCEL_ASYNCHRONOUS The
previous cancelability type.
This routine sets the cancelability type and returns the previous type
When the cancelability state is set to PTHREAD_CANCEL_DISABLE, (see
pthread_setcancelstate), a cancel cannot be delivered to the thread,
even if a cancelable routine is called or asynchronous cancelability
type is enabled.
When the cancelability state is set to PTHREAD_CANCEL_ENABLE, cancela‐
bility depends on the thread's cancelability type. If the thread's can‐
celability type is set to PTHREAD_CANCEL_DEFERRED, the thread can only
receive a cancel at specific cancellation points (including condition
waits, thread joins, and calls to pthread_testcancel.) If the thread's
cancelability type is PTHREAD_CANCEL_ASYNCHRONOUS, the thread can be
canceled at any point in its execution.
When a thread is created, the default cancelability type is
Warning If the asynchronous cancelability type is set, do not call any
routine unless it is explicitly documented as safe to be called with
the asynchronous cancelability type. Note that none of the general run-
time libraries and none of the DECthreads libraries are safe except for
pthread_setcanceltype, pthread_setcancelstate, and cma_alert_restore.
The asynchronous cancelability type should only be used when you have a
compute-bound section of code that carries no state and makes no rou‐
On successful completion, this routine returns the previous cancelabil‐
ity type in oldtype.
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 type is not PTHREAD_CAN‐
CEL_DEFERRED or PTHREAD_CANCEL_ASYNCHRONOUS.
Functions: pthread_cancel(3), pthread_setcancelstate(3), pthread_test‐
Manuals: Guide to DECthreads and Programmer's Guide