| sem_open.3 (fccedf067d9e77523b684f179b4aed07995f7b05) | sem_open.3 (26b6c45a92c8eae91cad4a7ce8935e08d2e5d368) |
|---|---|
| 1.\" Copyright (C) 2000 Jason Evans <jasone@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(s), this list of conditions and the following disclaimer as --- 12 unchanged lines hidden (view full) --- 21.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 23.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 24.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE 25.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 26.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27.\" 28.\" $FreeBSD$ | 1.\" Copyright (C) 2000 Jason Evans <jasone@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(s), this list of conditions and the following disclaimer as --- 12 unchanged lines hidden (view full) --- 21.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 23.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 24.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE 25.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 26.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27.\" 28.\" $FreeBSD$ |
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| 29.Dd January 15, 2003 30.Dt SEM_OPEN 3 31.Os 32.Sh NAME 33.Nm sem_open , 34.Nm sem_close , 35.Nm sem_unlink 36.Nd named semaphore operations 37.Sh LIBRARY 38.Lb libc 39.Sh SYNOPSIS 40.In semaphore.h | 30.Dd January 15, 2003 31.Dt SEM_OPEN 3 32.Os 33.Sh NAME 34.Nm sem_open , 35.Nm sem_close , 36.Nm sem_unlink 37.Nd named semaphore operations 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In semaphore.h |
| 41.Ft sem_t * 42.Fn sem_open "const char *name" "int oflag" "..." | 42.Ft "sem_t *" 43.Fn sem_open "const char *name" "int oflag" ... |
| 43.Ft int 44.Fn sem_close "sem_t *sem" 45.Ft int 46.Fn sem_unlink "const char *name" 47.Sh DESCRIPTION 48The 49.Fn sem_open 50function creates or opens the named semaphore specified by 51.Fa name . 52The returned semaphore may be used in subsequent calls to | 44.Ft int 45.Fn sem_close "sem_t *sem" 46.Ft int 47.Fn sem_unlink "const char *name" 48.Sh DESCRIPTION 49The 50.Fn sem_open 51function creates or opens the named semaphore specified by 52.Fa name . 53The returned semaphore may be used in subsequent calls to |
| 53.Fn sem_getvalue , 54.Fn sem_wait , 55.Fn sem_trywait , 56.Fn sem_post | 54.Xr sem_getvalue 3 , 55.Xr sem_wait 3 , 56.Xr sem_trywait 3 , 57.Xr sem_post 3 , |
| 57and 58.Fn sem_close . 59.Pp 60The following bits may be set in the 61.Fa oflag 62argument: 63.Bl -tag -width ".Dv O_CREAT" 64.It Dv O_CREAT 65Create the semaphore if it does not already exist. 66.Pp 67The third argument to the call to 68.Fn sem_open 69must be of type 70.Vt mode_t 71and specifies the mode for the semaphore. 72Only the | 58and 59.Fn sem_close . 60.Pp 61The following bits may be set in the 62.Fa oflag 63argument: 64.Bl -tag -width ".Dv O_CREAT" 65.It Dv O_CREAT 66Create the semaphore if it does not already exist. 67.Pp 68The third argument to the call to 69.Fn sem_open 70must be of type 71.Vt mode_t 72and specifies the mode for the semaphore. 73Only the |
| 73.Dv S_IWUSR , 74.Dv S_IWGRP , | 74.Dv S_IWUSR , S_IWGRP , |
| 75and 76.Dv S_IWOTH 77bits are examined; 78it is not possible to grant only 79.Dq read 80permission on a semaphore. 81The mode is modified according to the process's file creation 82mask; see --- 49 unchanged lines hidden (view full) --- 132.Sh ERRORS 133The 134.Fn sem_open 135function will fail if: 136.Bl -tag -width Er 137.It Bq Er EACCES 138The semaphore exists and the permissions specified by 139.Fa oflag | 75and 76.Dv S_IWOTH 77bits are examined; 78it is not possible to grant only 79.Dq read 80permission on a semaphore. 81The mode is modified according to the process's file creation 82mask; see --- 49 unchanged lines hidden (view full) --- 132.Sh ERRORS 133The 134.Fn sem_open 135function will fail if: 136.Bl -tag -width Er 137.It Bq Er EACCES 138The semaphore exists and the permissions specified by 139.Fa oflag |
| 140at the time it was created deny access to the this process. | 140at the time it was created deny access to this process. |
| 141.It Bq Er EACCES 142The semaphore does not exist, but permission to create it is denied. 143.It Bq Er EEXIST 144.Dv O_CREAT 145and 146.Dv O_EXCL 147are set but the semaphore already exists. 148.It Bq Er EINTR --- 79 unchanged lines hidden --- | 141.It Bq Er EACCES 142The semaphore does not exist, but permission to create it is denied. 143.It Bq Er EEXIST 144.Dv O_CREAT 145and 146.Dv O_EXCL 147are set but the semaphore already exists. 148.It Bq Er EINTR --- 79 unchanged lines hidden --- |