1.\" $NetBSD: _lwp_getprivate.2,v 1.6 2013/10/05 09:18:56 njoly Exp $ 2.\" 3.\" Copyright (c) 2003 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Jason R. Thorpe of Wasabi Systems, Inc. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd September 7, 2013 31.Dt _LWP_GETPRIVATE 2 32.Os 33.Sh NAME 34.Nm _lwp_getprivate , 35.Nm _lwp_setprivate 36.Nd get and set light-weight process private data 37.Sh LIBRARY 38.Lb libc 39.Sh SYNOPSIS 40.In lwp.h 41.Ft void * 42.Fn _lwp_getprivate void 43.Ft void 44.Fn _lwp_setprivate "void *ptr" 45.Sh DESCRIPTION 46.Fn _lwp_setprivate 47stores the pointer to private data 48.Fa ptr 49in a location private to the LWP. 50.Pp 51.Fn _lwp_getprivate 52returns the pointer to private data for the LWP. 53.Pp 54Some platforms provide alternative ways quicker than 55.Fn _lwp_getprivate 56to use the pointer. 57.Bl -tag -width amd64 58.It alpha 59The pointer can be retrieved by call_pal PAL_rdunique. 60.It amd64 61The base address of 62.Dv %fs 63register is set to the pointer so that the private data can be 64accessed using the selector. 65.It i386 66The base address of 67.Dv %gs 68register is set to the pointer so that the private data can be 69accessed using the selector. 70.It sparc 71.Dv %g7 72register is set to the pointer. 73.El 74.Sh ERRORS 75The 76.Fn _lwp_getprivate 77and 78.Fn _lwp_setprivate 79functions are always successful, and no return value is reserved to indicate 80an error. 81.Sh SEE ALSO 82.Xr _lwp_makecontext 3 83.Sh HISTORY 84The 85.Fn _lwp_getprivate 86and 87.Fn _lwp_setprivate 88system calls first appeared in 89.Nx 2.0 . 90