1.\" Copyright (c) 2002,2003 Alexey Zelkin <phantom@FreeBSD.org> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD: src/share/man/man3/pthread_attr_get_np.3,v 1.14 2007/10/22 10:08:00 ru Exp $ 26.\" 27.Dd December 12, 2020 28.Dt PTHREAD_ATTR_GET_NP 3 29.Os 30.Sh NAME 31.Nm pthread_attr_get_np , 32.Nm pthread_getattr_np 33.Nd get attributes of existing thread 34.Sh LIBRARY 35.Lb libpthread 36.Sh SYNOPSIS 37.In pthread.h 38.In pthread_np.h 39.Ft int 40.Fn pthread_attr_get_np "pthread_t thread" "pthread_attr_t *attr" 41.Ft int 42.Fn pthread_getattr_np "pthread_t thread" "pthread_attr_t *attr" 43.Sh DESCRIPTION 44The 45.Fn pthread_attr_get_np 46and 47.Fn pthread_getattr_np 48functions can be used to retrieve attributes of a running 49.Fa thread . 50Most fields of 51.Vt pthread_attr_t 52structure are exact values of attributes provided at thread creation 53time (as parameter to 54.Xr pthread_create 3 55function), except for the stack address. 56.Pp 57Value returned as 58.Fa attr 59is supposed to be used in conjunction with 60.Fn pthread_attr_get* 61functions to retrieve individual values from 62.Vt pthread_attr_t 63structure. 64Parameter 65.Fa attr 66should point to allocated memory area big enough to fit this structure. 67.Pp 68It is HIGHLY RECOMMENDED to use 69.Xr pthread_attr_init 3 70function to allocate attribute storage. 71.Fn pthread_getattr_np 72does this automatically. 73.Sh IMPLEMENTATION NOTES 74The 75.Fn pthread_attr_get_np 76function will always return a pointer to the thread's real stack address, 77regardless of its value in the original attributes structure. 78.Sh RETURN VALUES 79If successful, 80.Fn pthread_attr_get_np 81and 82.Fn pthread_getattr_np 83return 0. 84Otherwise, an error number is returned to indicate the error. 85.Sh EXAMPLES 86.Bd -literal 87size_t 88my_thread_stack_size(pthread_t pid) 89{ 90 pthread_attr_t attr; 91 size_t size; 92 93 pthread_attr_init(&attr); 94 pthread_attr_get_np(pid, &attr); 95 pthread_attr_getstacksize(&attr, &size); 96 pthread_attr_destroy(&attr); 97 return(size); 98} 99.Ed 100.Sh ERRORS 101The 102.Fn pthread_attr_get_np 103function will fail if: 104.Bl -tag -width Er 105.It Bq Er EINVAL 106Invalid value for one of given parameters. 107.It Bq Er ESRC 108No thread could be found corresponding to that specified by the given 109thread ID. 110.El 111.Sh SEE ALSO 112.Xr pthread_attr_destroy 3 , 113.Xr pthread_attr_getdetachstate 3 , 114.Xr pthread_attr_getinheritsched 3 , 115.Xr pthread_attr_getschedparam 3 , 116.Xr pthread_attr_getschedpolicy 3 , 117.Xr pthread_attr_getscope 3 , 118.Xr pthread_attr_getstack 3 , 119.Xr pthread_attr_getstackaddr 3 , 120.Xr pthread_attr_getstacksize 3 , 121.Xr pthread_attr_init 3 122.Sh AUTHORS 123The 124.Fn pthread_attr_get_np 125function and this manual page were written by 126.An Alexey Zelkin Aq Mt phantom@FreeBSD.org . 127