mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-20 11:11:24 +00:00
cabdddae57
This switches us to using -isoC-2011 as the symbol name which is used by groff and mdocml. It follows the change to 4 digit years as done with IEEE Std 1003 post-1999. MFC after: 2 weeks (groff changes only)
261 lines
6.9 KiB
Groff
261 lines
6.9 KiB
Groff
.\" Copyright (c) 2011 Ed Schouten <ed@FreeBSD.org>
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd December 26, 2011
|
|
.Dt THRD_CREATE 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm call_once ,
|
|
.Nm cnd_broadcast ,
|
|
.Nm cnd_destroy ,
|
|
.Nm cnd_init ,
|
|
.Nm cnd_signal ,
|
|
.Nm cnd_timedwait ,
|
|
.Nm cnd_wait ,
|
|
.Nm mtx_destroy ,
|
|
.Nm mtx_init ,
|
|
.Nm mtx_lock ,
|
|
.Nm mtx_timedlock ,
|
|
.Nm mtx_trylock ,
|
|
.Nm mtx_unlock ,
|
|
.Nm thrd_create ,
|
|
.Nm thrd_current ,
|
|
.Nm thrd_detach ,
|
|
.Nm thrd_equal ,
|
|
.Nm thrd_exit ,
|
|
.Nm thrd_join ,
|
|
.Nm thrd_sleep ,
|
|
.Nm thrd_yield ,
|
|
.Nm tss_create ,
|
|
.Nm tss_delete ,
|
|
.Nm tss_get ,
|
|
.Nm tss_set
|
|
.Nd C11 threads interface
|
|
.Sh LIBRARY
|
|
.Lb libstdthreads
|
|
.Sh SYNOPSIS
|
|
.In threads.h
|
|
.Ft void
|
|
.Fn call_once "once_flag *flag" "void (*func)(void)"
|
|
.Ft int
|
|
.Fn cnd_broadcast "cnd_t *cond"
|
|
.Ft void
|
|
.Fn cnd_destroy "cnd_t *cond"
|
|
.Ft int
|
|
.Fn cnd_init "cnd_t *cond"
|
|
.Ft int
|
|
.Fn cnd_signal "cnd_t *cond"
|
|
.Ft int
|
|
.Fn cnd_timedwait "cnd_t * restrict cond" "mtx_t * restrict mtx" "const struct timespec * restrict ts"
|
|
.Ft int
|
|
.Fn cnd_wait "cnd_t *cond" "mtx_t *mtx"
|
|
.Ft void
|
|
.Fn mtx_destroy "mtx_t *mtx"
|
|
.Ft int
|
|
.Fn mtx_init "mtx_t *mtx" "int type"
|
|
.Ft int
|
|
.Fn mtx_lock "mtx_t *mtx"
|
|
.Ft int
|
|
.Fn mtx_timedlock "mtx_t * restrict mtx" "const struct timespec * restrict ts"
|
|
.Ft int
|
|
.Fn mtx_trylock "mtx_t *mtx"
|
|
.Ft int
|
|
.Fn mtx_unlock "mtx_t *mtx"
|
|
.Ft int
|
|
.Fn thrd_create "thrd_t *thr" "int (*func)(void *)" "void *arg"
|
|
.Ft thrd_t
|
|
.Fn thrd_current "void"
|
|
.Ft int
|
|
.Fn thrd_detach "thrd_t thr"
|
|
.Ft int
|
|
.Fn thrd_equal "thrd_t thr0" "thrd_t thr1"
|
|
.Ft _Noreturn void
|
|
.Fn thrd_exit "int res"
|
|
.Ft int
|
|
.Fn thrd_join "thrd_t thr" "int *res"
|
|
.Ft int
|
|
.Fn thrd_sleep "const struct timespec *duration" "struct timespec *remaining"
|
|
.Ft void
|
|
.Fn thrd_yield "void"
|
|
.Ft int
|
|
.Fn tss_create "tss_t *key" "void (*dtor)(void *)"
|
|
.Ft void
|
|
.Fn tss_delete "tss_t key"
|
|
.Ft void *
|
|
.Fn tss_get "tss_t key"
|
|
.Ft int
|
|
.Fn tss_set "tss_t key" "void *val"
|
|
.Sh DESCRIPTION
|
|
As of
|
|
.St -isoC-2011 ,
|
|
the C standard includes an API for writing multithreaded applications.
|
|
Since POSIX.1 already includes a threading API that is used by virtually
|
|
any multithreaded application, the interface provided by the C standard
|
|
can be considered superfluous.
|
|
.Pp
|
|
In this implementation, the threading interface is therefore implemented
|
|
as a light-weight layer on top of existing interfaces.
|
|
The functions to which these routines are mapped, are listed in the
|
|
following table.
|
|
Please refer to the documentation of the POSIX equivalent functions for
|
|
more information.
|
|
.Bl -column ".Fn mtx_timedlock" ".Xr pthread_mutex_timedlock 3" -offset indent
|
|
.It Em Function Ta Em POSIX equivalent
|
|
.It Fn call_once Ta Xr pthread_once 3
|
|
.It Fn cnd_broadcast Ta Xr pthread_cond_broadcast 3
|
|
.It Fn cnd_destroy Ta Xr pthread_cond_destroy 3
|
|
.It Fn cnd_init Ta Xr pthread_cond_init 3
|
|
.It Fn cnd_signal Ta Xr pthread_cond_signal 3
|
|
.It Fn cnd_timedwait Ta Xr pthread_cond_timedwait 3
|
|
.It Fn cnd_wait Ta Xr pthread_cond_wait 3
|
|
.It Fn mtx_destroy Ta Xr pthread_mutex_destroy 3
|
|
.It Fn mtx_init Ta Xr pthread_mutex_init 3
|
|
.It Fn mtx_lock Ta Xr pthread_mutex_lock 3
|
|
.It Fn mtx_timedlock Ta Xr pthread_mutex_timedlock 3
|
|
.It Fn mtx_trylock Ta Xr pthread_mutex_trylock 3
|
|
.It Fn mtx_unlock Ta Xr pthread_mutex_unlock 3
|
|
.It Fn thrd_create Ta Xr pthread_create 3
|
|
.It Fn thrd_current Ta Xr pthread_self 3
|
|
.It Fn thrd_detach Ta Xr pthread_detach 3
|
|
.It Fn thrd_equal Ta Xr pthread_equal 3
|
|
.It Fn thrd_exit Ta Xr pthread_exit 3
|
|
.It Fn thrd_join Ta Xr pthread_join 3
|
|
.It Fn thrd_sleep Ta Xr nanosleep 2
|
|
.It Fn thrd_yield Ta Xr pthread_yield 3
|
|
.It Fn tss_create Ta Xr pthread_key_create 3
|
|
.It Fn tss_delete Ta Xr pthread_key_delete 3
|
|
.It Fn tss_get Ta Xr pthread_getspecific 3
|
|
.It Fn tss_set Ta Xr pthread_setspecific 3
|
|
.El
|
|
.Sh DIFFERENCES WITH POSIX EQUIVALENTS
|
|
The
|
|
.Fn thrd_exit
|
|
function returns an integer value to the thread calling
|
|
.Fn thrd_join ,
|
|
whereas the
|
|
.Fn pthread_exit
|
|
function uses a pointer.
|
|
.Pp
|
|
The mutex created by
|
|
.Fn mtx_init
|
|
can be of
|
|
.Fa type
|
|
.Dv mtx_plain
|
|
or
|
|
.Dv mtx_timed
|
|
to distinguish between a mutex that supports
|
|
.Fn mtx_timedlock .
|
|
This type can be
|
|
.Em or'd
|
|
with
|
|
.Dv mtx_recursive
|
|
to create a mutex that allows recursive acquisition.
|
|
These properties are normally set using
|
|
.Fn pthread_mutex_init Ns 's
|
|
.Fa attr
|
|
parameter.
|
|
.Sh RETURN VALUES
|
|
If successful, the
|
|
.Fn cnd_broadcast ,
|
|
.Fn cnd_init ,
|
|
.Fn cnd_signal ,
|
|
.Fn cnd_timedwait ,
|
|
.Fn cnd_wait ,
|
|
.Fn mtx_init ,
|
|
.Fn mtx_lock ,
|
|
.Fn mtx_timedlock ,
|
|
.Fn mtx_trylock ,
|
|
.Fn mtx_unlock ,
|
|
.Fn thrd_create ,
|
|
.Fn thrd_detach ,
|
|
.Fn thrd_equal ,
|
|
.Fn thrd_join ,
|
|
.Fn thrd_sleep ,
|
|
.Fn tss_create
|
|
and
|
|
.Fn tss_set
|
|
functions return
|
|
.Dv thrd_success .
|
|
Otherwise an error code will be returned to indicate the error.
|
|
.Pp
|
|
The
|
|
.Fn thrd_current
|
|
function returns the thread ID of the calling thread.
|
|
.Pp
|
|
The
|
|
.Fn tss_get
|
|
function returns the thread-specific data value associated with the
|
|
given
|
|
.Fa key .
|
|
If no thread-specific data value is associated with
|
|
.Fa key ,
|
|
then the value NULL is returned.
|
|
.Sh ERRORS
|
|
The
|
|
.Fn cnd_init
|
|
and
|
|
.Fn thrd_create
|
|
functions will fail if:
|
|
.Bl -tag -width thrd_timedout
|
|
.It Dv thrd_nomem
|
|
The system has insufficient memory.
|
|
.El
|
|
.Pp
|
|
The
|
|
.Fn cnd_timedwait
|
|
and
|
|
.Fn mtx_timedlock
|
|
functions will fail if:
|
|
.Bl -tag -width thrd_timedout
|
|
.It Dv thrd_timedout
|
|
The system time has reached or exceeded the time specified in
|
|
.Fa ts
|
|
before the operation could be completed.
|
|
.El
|
|
.Pp
|
|
The
|
|
.Fn mtx_trylock
|
|
function will fail if:
|
|
.Bl -tag -width thrd_timedout
|
|
.It Dv thrd_busy
|
|
The mutex is already locked.
|
|
.El
|
|
.Pp
|
|
In all other cases, these functions may fail by returning general error
|
|
code
|
|
.Dv thrd_error .
|
|
.Sh SEE ALSO
|
|
.Xr nanosleep 2 ,
|
|
.Xr pthread 3
|
|
.Sh STANDARDS
|
|
These functions are expected to conform to
|
|
.St -isoC-2011 .
|
|
.Sh HISTORY
|
|
These functions appeared in
|
|
.Fx 10.0 .
|
|
.Sh AUTHORS
|
|
.An Ed Schouten Aq ed@FreeBSD.org
|