NAME

    pthread_setasynccancel - Enables or disables the current
                             thread's asynchronous cancelability

 SYNOPSIS

     #include <pthread.h>

     int pthread_setasynccancel( int state );

 PARAMETERS

     state                State of asynchronous cancelability set for
                          the calling thread.  On return, receives the
                          prior state of asynchronous cancelability.
                          Valid values are as follows:

                          CANCEL_ON     Asynchronous cancelability is
                                        enabled.

                          CANCEL_OFF    Asynchronous cancelability is
                                        disabled.

 DESCRIPTION

 The pthread_setasynccancel()  routine enables or disables the current
 thread's asynchronous cancelability and returns the previous cancelabil-
 ity state to the state parameter.

 When general cancelability is set to CANCEL_OFF, a cancel cannot be
 delivered to the thread, even if a cancelable routine is called or asyn-
 chronous cancelability is enabled. When general cancelability is set to
 CANCEL_ON, cancelability depends on the state of the thread's asynchro-
 nous cancelability.

 When general cancelability is set to CANCEL_ON and asynchronous cancela-
 bility is set to CANCEL_OFF, the thread can only receive a cancel at
 specific cancellation points (for example, condition waits, thread
 joins, and calls to the pthread_testcancel() routine). If both general
 cancelability and asynchronous cancelability are set to CANCEL_ON, the
 thread can be canceled at any point in its execution.

 When a thread is created, the default asynchronous cancelability state
 is CANCEL_OFF.

 If you call this routine to enable asynchronous cancels, call it in a
 region of code where asynchronous delivery of cancels is disabled by a
 previous call to this routine. Do not call threads routines in regions
 of code where asynchronous delivery of cancels is enabled.  The previous
 state of asynchronous delivery can be restored later by another call to
 this routine.

 RETURN VALUES

 If the function fails, errno may be set to one of the following values:

    Return       Error      Description
    ___________________________________________________________
    CANCEL_ON               Asynchronous cancelability was on.

    CANCEL_OFF              Asynchronous cancelability was off.

    -1          [EINVAL]    The specified state is not CANCEL_ON
                            or CANCEL_OFF.

 RELATED INFORMATION

     FUNCTIONS: pthread_cancel
                pthread_setcancel
                pthread_testcancel