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.Dd October 12, 2021 26.Dt PTHREAD_ATTR_GET_NP 3 27.Os 28.Sh NAME 29.Nm pthread_attr_get_np 30.Nd get attributes of existent thread 31.Sh LIBRARY 32.Lb libpthread 33.Sh SYNOPSIS 34.In pthread_np.h 35.Ft int 36.Fn pthread_attr_get_np "pthread_t pid" "pthread_attr_t *dst" 37.Sh DESCRIPTION 38The 39.Fn pthread_attr_get_np 40function is used to get existent thread's attributes. 41Most fields of 42.Vt pthread_attr_t 43structure are exact values of attributes provided at thread creation 44time (as parameter to 45.Xr pthread_create 3 46function), except for the stack address. 47.Pp 48Value returned as 49.Fa dst 50is supposed to be used in conjunction with 51.Fn pthread_attr_get* 52functions to retrieve individual values from 53.Vt pthread_attr_t 54structure. 55Parameter 56.Fa dst 57should point to allocated memory area big enough to fit this structure. 58.Pp 59It is HIGHLY RECOMMENDED to use 60.Xr pthread_attr_init 3 61function to allocate attribute storage. 62.Sh IMPLEMENTATION NOTES 63The 64.Fn pthread_attr_get_np 65function will always return a pointer to the thread's real stack address, 66regardless of its value in the original attributes structure. 67.Sh RETURN VALUES 68If successful, 69.Fn pthread_attr_get_np 70function returns 0. 71Otherwise, an error number is returned to indicate the error. 72.Sh EXAMPLES 73.Bd -literal 74size_t 75my_thread_stack_size(pthread_t pid) 76{ 77 pthread_attr_t attr; 78 size_t size; 79 80 pthread_attr_init(&attr); 81 pthread_attr_get_np(pid, &attr); 82 pthread_attr_getstacksize(&attr, &size); 83 pthread_attr_destroy(&attr); 84 return(size); 85} 86.Ed 87.Sh ERRORS 88The 89.Fn pthread_attr_get_np 90function will fail if: 91.Bl -tag -width Er 92.It Bq Er EINVAL 93Invalid value for one of given parameters. 94.It Bq Er ESRCH 95No thread could be found corresponding to that specified by the given 96thread ID. 97.El 98.Sh SEE ALSO 99.Xr pthread_attr_destroy 3 , 100.Xr pthread_attr_getdetachstate 3 , 101.Xr pthread_attr_getinheritsched 3 , 102.Xr pthread_attr_getschedparam 3 , 103.Xr pthread_attr_getschedpolicy 3 , 104.Xr pthread_attr_getscope 3 , 105.Xr pthread_attr_getstack 3 , 106.Xr pthread_attr_getstackaddr 3 , 107.Xr pthread_attr_getstacksize 3 , 108.Xr pthread_attr_init 3 , 109.Xr pthread_np 3 110.Sh AUTHORS 111The 112.Fn pthread_attr_get_np 113function and this manual page were written by 114.An Alexey Zelkin Aq Mt phantom@FreeBSD.org . 115