pthread.pod

Linux下的中文输入法

I<pthread_create()>.
Using these routines does not affect the current running thread.

=head1 FUTURE DIRECTIONS

None.

=head1 SEE ALSO

I<pthread_attr_init()>,
I<pthread_attr_setscope()>,
I<pthread_attr_setinheritsched()>,
I<pthread_attr_setschedpolicy()>,
I<pthread_create()>,
I<<pthread.h>>,
I<pthread_setschedparam()>,
I<<sched.h>>.

=head1 ______________________________________________________________________

=head1 NAME

B<pthread_attr_setschedpolicy,> B<pthread_attr_getschedpolicy>
- set and get schedpolicy attribute
(B<REALTIME THREADS>)

=head1 SYNOPSIS

#include <pthread.h>

int pthread_attr_setschedpolicy(pthread_attr_t *I<attr>, int I<policy>);
int pthread_attr_getschedpolicy(const pthread_attr_t *I<attr>,
int *I<policy>);

=head1 DESCRIPTION

The functions
I<pthread_attr_setschedpolicy()>
and
I<pthread_attr_getschedpolicy()>,
respectively, set and get the
I<schedpolicy>
attribute in the
I<attr>
argument.

The supported values of
I<policy>
include SCHED_FIFO, SCHED_RR and SCHED_OTHER,
which are defined by the header
I<<sched.h>>.
When threads executing with the scheduling policy
SCHED_FIFO or SCHED_RR are waiting on a mutex,
they acquire the mutex in priority order when the mutex is unlocked.

=head1 RETURN VALUE

If successful, the
I<pthread_attr_setschedpolicy()>
and
I<pthread_attr_getschedpolicy()>
functions return zero.
Otherwise, an error number is returned to indicate the error.

=head1 ERRORS

The
I<pthread_attr_setschedpolicy()>
and
I<pthread_attr_getschedpolicy()>
functions will fail if:

=over 4

=item [ENOSYS]

The option _POSIX_THREAD_PRIORITY_SCHEDULING is not defined and the
implementation does not support the function.

=back

The
I<pthread_attr_setschedpolicy()>
function may fail if:

=over 4

=item [EINVAL]

The value of the attribute being set is not valid.

=item [ENOTSUP]

An attempt was made to set the attribute to an unsupported value.

=back

=head1 EXAMPLES

None.

=head1 APPLICATION USAGE

After these attributes have been set, a thread can be created with
the specified attributes using
I<pthread_create()>.
Using these routines does not affect the current running thread.

=head1 FUTURE DIRECTIONS

None.

=head1 SEE ALSO

I<pthread_attr_init()>,
I<pthread_attr_setscope()>,
I<pthread_attr_setinheritsched()>,
I<pthread_attr_setschedparam()>,
I<pthread_create()>,
I<<pthread.h>>,
I<pthread_setschedparam()>,
I<<sched.h>>.

=head1 ______________________________________________________________________

=head1 NAME

B<pthread_attr_setscope,> B<pthread_attr_getscope>
- set and get contentionscope attribute
(B<REALTIME THREADS>)

=head1 SYNOPSIS

#include <pthread.h>

int pthread_attr_setscope(pthread_attr_t *I<attr>, int I<contentionscope>);
int pthread_attr_getscope(const pthread_attr_t *I<attr>,
int *I<contentionscope>);

=head1 DESCRIPTION

The
I<pthread_attr_setscope()>
and
I<pthread_attr_getscope()>
functions are used to set and get the
I<contentionscope>
attribute in the
I<attr>
object.

The
I<contentionscope>
attribute may have the values
PTHREAD_SCOPE_SYSTEM,
signifying system scheduling contention scope,
or PTHREAD_SCOPE_PROCESS,
signifying process scheduling contention scope.
The symbols PTHREAD_SCOPE_SYSTEM and PTHREAD_SCOPE_PROCESS
are defined by the header
I<<pthread.h>>.

=head1 RETURN VALUE

If successful, the
I<pthread_attr_setscope()>
and
I<pthread_attr_getscope()>
functions return zero.
Otherwise, an error number is returned to indicate the error.

=head1 ERRORS

The
I<pthread_attr_setscope()>
and
I<pthread_attr_getscope()>
functions will fail if:

=over 4

=item [ENOSYS]

The option _POSIX_THREAD_PRIORITY_SCHEDULING is not defined and the
implementation does not support the function.

=back

The
I<pthread_attr_setscope()>,
function may fail if:

=over 4

=item [EINVAL]

The value of the attribute being set is not valid.

=item [ENOTSUP]

An attempt was made to set the attribute to an unsupported value.

=back

=head1 EXAMPLES

None.

=head1 APPLICATION USAGE

After these attributes have been set, a thread can be created with
the specified attributes using
I<pthread_create()>.
Using these routines does not affect the current running thread.

=head1 FUTURE DIRECTIONS

None.

=head1 SEE ALSO

I<pthread_attr_init()>,
I<pthread_attr_setinheritsched()>,
I<pthread_attr_setschedpolicy()>,
I<pthread_attr_setschedparam()>,
I<pthread_create()>,
I<<pthread.h>>,
I<pthread_setschedparam()>,
I<<sched.h>>.

=head1 ______________________________________________________________________

=head1 NAME

B<pthread_attr_setstackaddr,> B<pthread_attr_getstackaddr>
- set and get stackaddr attribute

=head1 SYNOPSIS

#include <pthread.h>

int pthread_attr_setstackaddr(pthread_attr_t *I<attr>, void *I<stackaddr>);
int pthread_attr_getstackaddr(const pthread_attr_t *I<attr>,
void **I<stackaddr>);

=head1 DESCRIPTION

The functions
I<pthread_attr_setstackaddr()>
and
I<pthread_attr_getstackaddr()>,
respectively, set and get the thread creation
I<stackaddr>
attribute in the
I<attr>
object.

The
I<stackaddr>
attribute specifies the location of storage
to be used for the created thread's stack.
The size of the storage is at least PTHREAD_STACK_MIN.

=head1 RETURN VALUE

Upon successful completion,
I<pthread_attr_setstackaddr()>
and
I<pthread_attr_getstackaddr()>
return a value of 0.
Otherwise, an error number is returned to indicate the error.

The
I<pthread_attr_getstackaddr()>
function stores the
I<stackaddr>
attribute value in
I<stackaddr>
if successful.

=head1 ERRORS

No errors are defined.

These functions will not return an error code of [EINTR].

=head1 EXAMPLES

None.

=head1 APPLICATION USAGE

None.

=head1 FUTURE DIRECTIONS

None.

=head1 SEE ALSO

I<pthread_attr_init()>,
I<pthread_attr_setdetachstate()>,
I<pthread_attr_setstacksize()>,
I<pthread_create()>,
I<<limits.h>>,
I<<pthread.h>>.

=head1 ______________________________________________________________________

=head1 NAME

B<pthread_attr_setstacksize,> B<pthread_attr_getstacksize>
- set and get stacksize attribute

=head1 SYNOPSIS

#include <pthread.h>

int pthread_attr_setstacksize(pthread_attr_t *I<attr>, size_t I<stacksize>);
int pthread_attr_getstacksize(const pthread_attr_t *I<attr>,
size_t *I<stacksize>);

=head1 DESCRIPTION

The functions
I<pthread_attr_setstacksize()>
and
I<pthread_attr_getstacksize()>,
respectively, set and get the thread creation
I<stacksize>
attribute in the
I<attr>
object.

The
I<stacksize>
attribute defines the minimum stack size (in bytes) allocated for
the created threads stack.

=head1 RETURN VALUE

Upon successful completion,
I<pthread_attr_setstacksize()>
and
I<pthread_attr_getstacksize()>
return a value of 0.
Otherwise, an error number is returned to indicate the error.
The
I<pthread_attr_getstacksize()>
function stores the
I<stacksize>
attribute value in
I<stacksize>
if successful.

=head1 ERRORS

The
I<pthread_attr_setstacksize()>
function will fail if:

=over 4

=item [EINVAL]

The value of
I<stacksize>
is less than PTHREAD_STACK_MIN or exceeds a system-imposed limit.

=back

These functions will not return an error code of [EINTR].

=head1 EXAMPLES

None.

=head1 APPLICATION USAGE

None.

=head1 FUTURE DIRECTIONS

None.

=head1 SEE ALSO

I<pthread_attr_init()>,
I<pthread_attr_setstackaddr()>,
I<pthread_attr_setdetachstate()>,
I<pthread_create()>,
I<<limits.h>>,
I<<pthread.h>>.

=head1 ______________________________________________________________________

=head1 NAME

B<pthread_cancel> - cancel execution of a thread

=head1 SYNOPSIS

#include <pthread.h>

int pthread_cancel(pthread_t I<thread>);

=head1 DESCRIPTION

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

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

=head1 RETURN VALUE

If successful, the
I<pthread_cancel()>
function returns zero.
Otherwise, an error number is returned to indicate the error.

=head1 ERRORS

The
I<pthread_cancel()>
function may fail if:

=over 4

=item [ESRCH]

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

=back

The
I<pthread_cancel()>
function will not return an error code of [EINTR].

=head1 EXAMPLES

None.

=head1 APPLICATION USAGE

None.

=head1 FUTURE DIRECTIONS

None.

=head1 SEE ALSO

I<pthread_exit()>,
I<pthread_join()>,
I<pthread_setcancelstate()>,
I<pthread_cond_wait()>,
I<pthread_cond_timedwait()>,
I<<pthread.h>>.

=head1 ______________________________________________________________________

=head1 NAME

B<pthread_cleanup_push,> B<pthread_cleanup_pop> - establish cancellation handlers

=head1 SYNOPSIS

#include <pthread.h>

void pthread_cleanup_push(void (*I<routine>)(void*), void *I<arg>);
void pthread_cleanup_pop(int I<execute>);

=head1 DESCRIPTION

The
I<pthread_cleanup_push()>
function pushes the specified cancellation cleanup handler
I<routine>
onto the calling thread's cancellation cleanup stack.
The cancellation cleanup handler is popped from the
cancellation cleanup stack and invoked with the argument
I<arg>
when: (a) the thread exits (that is, calls
I<pthread_exit()>),
(b) the thread acts upon a cancellation request, or
(c) the thread calls
I<pthread_cleanup_pop()>
with a non-zero
I<execute>
argument.

The
I<pthread_cleanup_pop()>
function removes the routine at the top of the calling thread's
cancellation cleanup stack and optionally invokes it (if
I<execute>
is non-zero).

These functions may be implemented as macros and will
appear as statements and in pairs within the same lexical scope (that is, the
I<pthread_cleanup_push()>
macro may be thought to expand to a token list whose first
token is
B<`{'>
with
I<pthread_cleanup_pop()>
expanding to a token list whose last token is the corresponding
B<`}'>.

The effect of calling
I<longjmp()>
or
I<siglongjmp()>
is undefined if there have been any calls to
I<pthread_cleanup_push()>
or
I<pthread_cleanup_pop()>
made without the matching call
since the jump buffer was filled.
The effect of calling
I<longjmp()>
or
I<siglongjmp()>
from inside a cancellation cleanup handler is also
undefined unless the jump buffer was also filled in the
cancellation cleanup handler.

=head1 RETURN VALUE

The
I<pthread_cleanup_push()>
and
I<pthread_cleanup_pop()>
functions return no value.

=head1 ERRORS

No errors are defined.

These functions will not return an error code of [EINTR].

=head1 EXAMPLES

None.

=head1 APPLICATION USAGE