Libc-498.1.1.tar.gz

[apple/libc.git] / pthreads / pthread_attr.3

.\" Copyright (C) 2000 Jason Evans <jasone@FreeBSD.org>.
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.\" $FreeBSD: src/lib/libc_r/man/pthread_attr.3,v 1.4.2.5 2001/08/17 15:42:51 ru Exp $
.Dd April 28, 2000
.Dt PTHREAD_ATTR 3
.Os
.Sh NAME
.Nm pthread_attr_destroy ,
.Nm pthread_attr_getdetachstate ,
.Nm pthread_attr_getinheritsched ,
.Nm pthread_attr_getschedparam ,
.Nm pthread_attr_getschedpolicy ,
.Nm pthread_attr_getscope ,
.Nm pthread_attr_getstackaddr ,
.Nm pthread_attr_getstacksize ,
.Nm pthread_attr_init ,
.Nm pthread_attr_setdetachstate ,
.Nm pthread_attr_setinheritsched ,
.Nm pthread_attr_setschedparam ,
.Nm pthread_attr_setschedpolicy ,
.Nm pthread_attr_setscope ,
.Nm pthread_attr_setstackaddr ,
.Nm pthread_attr_setstacksize
.Nd thread attribute operations
.Sh SYNOPSIS
.Fd #include <pthread.h>
.Ft int
.Fo pthread_attr_destroy
.Fa "pthread_attr_t *attr"
.Fc
.Ft int
.Fo pthread_attr_getdetachstate
.Fa "const pthread_attr_t *attr"
.Fa "int *detachstate"
.Fc
.Ft int
.Fo pthread_attr_getinheritsched
.Fa "const pthread_attr_t *restrict attr"
.Fa "int *restrict inheritsched"
.Fc
.Ft int
.Fo pthread_attr_getschedparam
.Fa "const pthread_attr_t *restrict attr"
.Fa "struct sched_param *restrict param"
.Fc
.Ft int
.Fo pthread_attr_getschedpolicy
.Fa "const pthread_attr_t *restrict attr"
.Fa "int *restrict policy"
.Fc
.Ft int
.Fo pthread_attr_getscope
.Fa "const pthread_attr_t *restrict attr"
.Fa "int *restrict contentionscope"
.Fc
.Ft int
.Fo pthread_attr_getstackaddr
.Fa "const pthread_attr_t *restrict attr"
.Fa "void **restrict stackaddr"
.Fc
.Ft int
.Fo pthread_attr_getstacksize
.Fa "const pthread_attr_t *restrict attr"
.Fa "size_t *restrict stacksize"
.Fc
.Ft int
.Fo pthread_attr_init
.Fa "pthread_attr_t *attr"
.Fc
.Ft int
.Fo pthread_attr_setdetachstate
.Fa "pthread_attr_t *attr"
.Fa "int detachstate"
.Fc
.Ft int
.Fo pthread_attr_setinheritsched
.Fa "pthread_attr_t *attr"
.Fa "int inheritsched"
.Fc
.Ft int
.Fo pthread_attr_setschedparam
.Fa "pthread_attr_t *restrict attr"
.Fa "const struct sched_param *restrict param"
.Fc
.Ft int
.Fo pthread_attr_setschedpolicy
.Fa "pthread_attr_t *attr"
.Fa "int policy"
.Fc
.Ft int
.Fo pthread_attr_setscope
.Fa "pthread_attr_t *attr"
.Fa "int contentionscope"
.Fc
.Ft int
.Fo pthread_attr_setstackaddr
.Fa "pthread_attr_t *attr"
.Fa "void *stackaddr"
.Fc
.Ft int
.Fo pthread_attr_setstacksize
.Fa "pthread_attr_t *attr"
.Fa "size_t stacksize"
.Fc
.Sh DESCRIPTION
Thread attributes are used to specify parameters to
.Fn pthread_create .
One attribute object can be used in multiple calls to
.Fn pthread_create ,
with or without modifications between calls.
.Pp
The
.Fn pthread_attr_init
function initializes
.Fa attr
with all the default thread attributes.
.Pp
The
.Fn pthread_attr_destroy
function destroys
.Fa attr .
.Pp
The
.Fn pthread_attr_set*
functions set the attribute that corresponds to each function name.
.Pp
The
.Fn pthread_attr_get*
functions copy the value of the attribute that corresponds to each function name
to the location pointed to by the second function parameter.
.Sh RETURN VALUES
If successful, these functions return 0.
Otherwise, an error number is returned to indicate the error.
.Sh ERRORS
.Fn pthread_attr_init
will fail if:
.Bl -tag -width Er
.\" ========
.It Bq Er ENOMEM
Out of memory.
.El
.Pp
.Fn pthread_attr_destroy
will fail if:
.Bl -tag -width Er
.\" ========
.It Bq Er EINVAL
Invalid value for
.Fa attr .
.El
.Pp
.Fn pthread_attr_setstacksize
will fail if:
.Bl -tag -width Er
.\" ========
.It Bq Er EINVAL
Invalid value for
.Fa attr .
.\" ========
.It Bq Er EINVAL
.Fa stacksize
is less than
.Dv PTHREAD_STACK_MIN .
.\" ========
.It Bq Er EINVAL
.Fa stacksize
is not a multiple of the system page size.
.El
.Pp
.Fn pthread_attr_setdetachstate
will fail if:
.Bl -tag -width Er
.\" ========
.It Bq Er EINVAL
Invalid value for
.Fa attr
or
.Fa detachstate .
.El
.Pp
.Fn pthread_attr_setinheritsched
will fail if:
.Bl -tag -width Er
.\" ========
.It Bq Er EINVAL
Invalid value for
.Fa attr .
.El
.Pp
.Fn pthread_attr_setschedparam
will fail if:
.Bl -tag -width Er
.\" ========
.It Bq Er EINVAL
Invalid value for
.Fa attr .
.\" ========
.It Bq Er ENOTSUP
Invalid value for
.Fa param .
.El
.Pp
.Fn pthread_attr_setschedpolicy
will fail if:
.Bl -tag -width Er
.\" ========
.It Bq Er EINVAL
Invalid value for
.Fa attr .
.It Bq Er ENOTSUP
Invalid or unsupported value for
.Fa policy .
.El
.Pp
.Fn pthread_attr_setscope
will fail if:
.Bl -tag -width Er
.\" ========
.It Bq Er EINVAL
Invalid value for
.Fa attr .
.\" ========
.It Bq Er ENOTSUP
Invalid or unsupported value for
.Fa contentionscope .
.El
.Sh SEE ALSO
.Xr pthread_create 3
.Sh STANDARDS
.Fn pthread_attr_init ,
.Fn pthread_attr_destroy ,
.Fn pthread_attr_setstacksize ,
.Fn pthread_attr_getstacksize ,
.Fn pthread_attr_setstackaddr ,
.Fn pthread_attr_getstackaddr ,
.Fn pthread_attr_setdetachstate ,
and
.Fn pthread_attr_getdetachstate
conform to
.St -p1003.1-96
.Pp
.Fn pthread_attr_setinheritsched ,
.Fn pthread_attr_getinheritsched ,
.Fn pthread_attr_setschedparam ,
.Fn pthread_attr_getschedparam ,
.Fn pthread_attr_setschedpolicy ,
.Fn pthread_attr_getschedpolicy ,
.Fn pthread_attr_setscope ,
and
.Fn pthread_attr_getscope
conform to
.St -susv2