1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
.\"
.\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for
.\" permission to reproduce portions of its copyrighted documentation.
.\" Original documentation from The Open Group can be obtained online at
.\" http://www.opengroup.org/bookstore/.
.\"
.\" The Institute of Electrical and Electronics Engineers and The Open
.\" Group, have given us permission to reprint portions of their
.\" documentation.
.\"
.\" In the following statement, the phrase ``this text'' refers to portions
.\" of the system documentation.
.\"
.\" Portions of this text are reprinted and reproduced in electronic form
.\" in the SunOS Reference Manual, from IEEE Std 1003.1, 2004 Edition,
.\" Standard for Information Technology -- Portable Operating System
.\" Interface (POSIX), The Open Group Base Specifications Issue 6,
.\" Copyright (C) 2001-2004 by the Institute of Electrical and Electronics
.\" Engineers, Inc and The Open Group. In the event of any discrepancy
.\" between these versions and the original IEEE and The Open Group
.\" Standard, the original IEEE and The Open Group Standard is the referee
.\" document. The original Standard can be obtained online at
.\" http://www.opengroup.org/unix/online.html.
.\"
.\" This notice shall appear on any product containing this material.
.\"
.\" The contents of this file are subject to the terms of the
.\" Common Development and Distribution License (the "License").
.\" You may not use this file except in compliance with the License.
.\"
.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
.\" or http://www.opensolaris.org/os/licensing.
.\" See the License for the specific language governing permissions
.\" and limitations under the License.
.\"
.\" When distributing Covered Code, include this CDDL HEADER in each
.\" file and include the License file at usr/src/OPENSOLARIS.LICENSE.
.\" If applicable, add the following below this CDDL HEADER, with the
.\" fields enclosed by brackets "[]" replaced with your own identifying
.\" information: Portions Copyright [yyyy] [name of copyright owner]
.\"
.\"
.\" Copyright (c) 2001, The IEEE and The Open Group. All Rights Reserved.
.\" Portions Copyright (c) 2004, Sun Microsystems, Inc. All Rights Reserved.
.\"
.TH SEM.H 3HEAD "Sep 10, 2004"
.SH NAME
sem.h, sem \- semaphore facility
.SH SYNOPSIS
.LP
.nf
#include <\fBsys/sem.h\fR>
.fi
.SH DESCRIPTION
.sp
.LP
The <\fBsys/sem.h\fR> header defines the following constants and structures.
.sp
.LP
Semaphore operation flags:
.sp
.ne 2
.na
\fB\fBSEM_UNDO\fR\fR
.ad
.RS 12n
Set up adjust on exit entry.
.RE
.sp
.LP
Command definitions for the \fBsemctl()\fR function are provided as listed
below. See \fBsemctl\fR(2).
.sp
.ne 2
.na
\fB\fBGETNCNT\fR\fR
.ad
.RS 11n
Get \fBsemncnt\fR.
.RE
.sp
.ne 2
.na
\fB\fBGETPID\fR\fR
.ad
.RS 11n
Get \fBsempid\fR.
.RE
.sp
.ne 2
.na
\fB\fBGETVAL\fR\fR
.ad
.RS 11n
Get \fBsemval\fR.
.RE
.sp
.ne 2
.na
\fB\fBGETALL\fR\fR
.ad
.RS 11n
Get all cases of \fBsemval\fR.
.RE
.sp
.ne 2
.na
\fB\fBGETZCNT\fR\fR
.ad
.RS 11n
Get \fBsemzcnt\fR.
.RE
.sp
.ne 2
.na
\fB\fBSETVAL\fR\fR
.ad
.RS 11n
Set \fBsemval\fR.
.RE
.sp
.ne 2
.na
\fB\fBSETALL\fR\fR
.ad
.RS 11n
Set all cases of \fBsemval\fR.
.RE
.sp
.LP
The \fBsemid_ds\fR structure contains the following members:
.sp
.in +2
.nf
struct ipc_perm sem_perm /* operation permission structure */
unsigned short sem_nsems /* number of semaphores in set */
time_t sem_otime /* last \fBsemop()\fR time */
time_t sem_ctime /* last time changed by \fBsemctl()\fR */
.fi
.in -2
.sp
.LP
The \fBpid_t\fR, \fBtime_t\fR, \fBkey_t\fR, and \fBsize_t\fR types are defined
as described in <\fBsys/types.h\fR>. See \fBtypes.h\fR(3HEAD).
.sp
.LP
A semaphore is represented by an anonymous structure containing the following
members:
.sp
.in +2
.nf
unsigned short semval /* semaphore value */
pid_t sempid /* process ID of last operation */
unsigned short semncnt /* number of processes waiting for \fBsemval\fR
to become greater than current value */
unsigned short semzcnt /* number of processes waiting for \fBsemval\fR
to become 0 */
.fi
.in -2
.sp
.LP
The \fBsembuf\fR structure contains the following members:
.sp
.in +2
.nf
unsigned short sem_num /* semaphore number */
short sem_op /* semaphore operation */
short sem_flg /* operation flags */
.fi
.in -2
.sp
.LP
All of the symbols from <\fBsys/ipc.h\fR> are defined when this header is
included. See \fBipc.h\fR(3HEAD).
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp
.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE ATTRIBUTE VALUE
_
Interface Stability Standard
.TE
.SH SEE ALSO
.sp
.LP
.BR semctl (2),
.BR semget (2),
.BR semop (2),
.BR ipc.h (3HEAD),
.BR types.h (3HEAD),
.BR attributes (7),
.BR standards (7)
|
