freebsd-nq/lib/libc_r/man/pthread_cancel.3
Alfred Perlstein 7285bccf1a add pthread_cancel, obtained from OpenBSD.
eischen (Daniel Eischen) added wrappers to protect against cancled
threads orphaning internal resources.

the cancelability code is still a bit fuzzy but works for test
programs of my own, OpenBSD's and some examples from ORA's books.

add readdir_r to both libc and libc_r

add some 'const' attributes to function parameters

Reviewed by: eischen, jasone
1999-11-28 05:38:13 +00:00

71 lines
1.8 KiB
Groff

.\" $FreeBSD$
.Dd January 17, 1999
.Dt PTHREAD_CANCEL 3
.Os
.Sh NAME
.Nm pthread_cancel
.Nd cancel execution of a thread
.Sh SYNOPSIS
.Fd #include <pthread.h>
.Ft int
.Fn pthread_cancel "pthread_t thread"
.Sh DESCRIPTION
The
.Fn pthread_cancel
function requests that
.Fa thread
be canceled. The target thread's cancelability state and type determines
when the cancellation takes effect. When the cancellation is acted on,
the cancellation cleanup handlers for
.Fa thread
are called. When the last cancellation cleanup handler returns,
the thread-specific data destructor functions will be called for
.Fa thread .
When the last destructor function returns,
.Fa thread
will be terminated.
.Pp
The cancellation processing in the target thread runs asynchronously with
respect to the calling thread returning from
.Fn pthread_cancel .
.Pp
A status of
.Dv PTHREAD_CANCELED
is made available to any threads joining with the target. The symbolic
constant
.Dv PTHREAD_CANCELED
expands to a constant expression of type
.Ft "(void *)" ,
whose value matches no pointer to an object in memory nor the value
.Dv NULL .
.Sh RETURN VALUES
If successful, the
.Fn pthread_cancel
functions will return zero. Otherwise an error number will be returned to
indicate the error.
.Sh ERRORS
.Fn pthread_cancel
will fail if:
.Bl -tag -width Er
.It Bq Er ESRCH
No thread could be found corresponding to that specified by the given
thread ID.
.El
.Sh SEE ALSO
.Xr pthread_cleanup_pop 3 ,
.Xr pthread_cleanup_push 3 ,
.Xr pthread_exit 3 ,
.Xr pthread_join 3 ,
.Xr pthread_setcancelstate 3 ,
.Xr pthread_setcanceltype 3 ,
.Xr pthread_testcancel 3
.Sh STANDARDS
.Fn pthread_cancel
conforms to ISO/IEC 9945-1 ANSI/IEEE
.Pq Dq Tn POSIX
Std 1003.1 Second Edition 1996-07-12.
.Sh AUTHORS
This man page was written by
.An David Leonard <d@openbsd.org>
for the OpenBSD implementation of pthread_cancel.