1.\" Copyright (c) 2004 Michael Telahun Makonnen 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.\" $FreeBSD$ 26.\" 27.\" Note: The date here should be updated whenever a non-trivial 28.\" change is made to the manual page. 29.Dd January 22, 2004 30.Dt PTHREAD_SPIN_INIT 3 PTHREAD_SPIN_DESTROY 3 31.Os 32.Sh NAME 33.Nm pthread_spin_init pthread_spin_destroy 34.Nd "initialize or destroy a spin lock" 35.Sh LIBRARY 36.Lb libpthread 37.Lb libthr 38.Sh SYNOPSIS 39.In pthread.h 40.Ft int 41.Fn pthread_spin_init "pthread_spinlock_t *lock" "int pshared" 42.Ft int 43.Fn pthread_spin_destroy "pthread_spinlock_t *lock" 44.Sh DESCRIPTION 45The 46.Fn pthread_spin_init 47function will initialize 48.Fa lock 49to an unlocked state and 50allocate any resources necessary to begin using it. 51If 52.Fa pshared 53is set to 54.Dv PTHREAD_PROCESS_SHARED 55any thread, 56whether belonging to the process in which the spinlock was created or not, 57that has access to the memory area where 58.Fa lock 59resides can use 60.Fa lock . 61If it is set to 62.Dv PTHREAD_PROCESS_PRIVATE 63it can only be used by threads within the same process. 64.Pp 65The 66.Fn pthread_spin_destroy 67function will destroy 68.Fa lock 69and release any resources that may have been allocated on its behalf. 70.Pp 71.Sh DIAGNOSTICS 72If successful, 73both 74.Fn pthread_spin_init 75and 76.Fn pthread_spin_destroy 77will return zero. 78Otherwise an error number will be returned to indicate the error. 79.Pp 80Neither of these functions will return EINTR. 81.Pp 82.Sh ERRORS 83The 84.Fn pthread_spin_init 85and 86.Fn pthread_spin_destroy 87functions will fail if: 88.Bl -tag -width Er 89.It Bq Er EBUSY 90An attempt to initialize or destroy 91.Fa lock 92while it is in use. 93.It Bq Er EINVAL 94The value specified by 95.Fa lock 96is invalid. 97.El 98.Pp 99The 100.Fn pthread_spin_init 101function will fail if: 102.Bl -tag -width Er 103.It Bq Er EAGAIN 104Insufficient resources, 105other than memory, 106to initialize 107.Fa lock . 108.It Bq Er ENOMEM 109Insufficient memory to initialize 110.Fa lock . 111.El 112.Sh SEE ALSO 113.Xr pthread_spin_lock 3 , 114.Xr pthread_spin_unlock 3 115.Sh HISTORY 116The 117.Fn pthread_spin_init 118and 119.Fn pthread_spin_destroy 120functions first appeared in 121.Lb libpthread 122in 123.Fx 5.2 , 124and in 125.Lb libthr 126in 127.Fx 5.3 . 128.Sh BUGS 129The implementation of 130.Fn pthread_spin_init 131does not fully conform to 132.St -p1003.2 133because the 134.Fa pshared 135argument is ignored in 136.Lb libthr , 137and in 138.Lb libpthread 139if any value other than 140.Dv PTHREAD_PROCESSES_PRIVATE 141is specified it returns EINVAL. 142