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
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
|
.\"
.\" 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 1989 AT&T
.\" Copyright (c) 2001, The IEEE and The Open Group. All Rights Reserved.
.\" Copyright (c) 2002, Sun Microsystems, Inc. All Rights Reserved.
.\" Copyright (c) 2014, Joyent, Inc.
.\"
.TH MKFIFO 3C "June 18, 2021"
.SH NAME
mkfifo, mkfifoat \- make a FIFO special file
.SH SYNOPSIS
.nf
#include <sys/types.h>
#include <sys/stat.h>
\fBint\fR \fBmkfifo\fR(\fBconst char *\fR\fIpath\fR, \fBmode_t\fR \fImode\fR);
.fi
.LP
.nf
\fBint\fR \fBmkfifoat\fR(\fBint\fR \fIfd\fR, \fBconst char *\fR\fIpath\fR, \fBmode_t\fR \fImode\fR);
.fi
.SH DESCRIPTION
The \fBmkfifo()\fR and \fBmkfifoat()\fR functions create a new FIFO special file
named by the pathname pointed to by \fIpath\fR. The file permission bits of the
new FIFO are initialized from \fImode\fR. The file permission bits of the
\fImode\fR argument are modified by the process's file creation mask (see
\fBumask\fR(2)). Bits other than the file permission bits in \fImode\fR are
ignored.
.sp
.LP
If \fIpath\fR names a symbolic link, \fBmkfifo()\fR and \fBmkfifoat()\fR fail
and set \fBerrno\fR to \fBEEXIST\fR.
.sp
.LP
The FIFO's user ID is set to the process's effective user ID. The FIFO's group
ID is set to the group ID of the parent directory or to the effective group ID
of the process.
.sp
.LP
The \fBmkfifoat()\fR function is equivalent to \fBmkfifo()\fR; however, if
\fIpath\fR is a relative path, then it is resolved start at the directory
represented by \fIfd\fR. \fIfd\fR may be set to the special value of
\fBAT_FDCWD\fR which indicates that the current working directory should be used
to start resolving \fIpath\fR.
.sp
.LP
The \fBmkfifo()\fR function calls \fBmknod\fR(2) to create the file. The
\fBmkfifoat()\fR function calls \fBmknodat\fR(2) to create the file.
.sp
.LP
Upon successful completion, \fBmkfifo()\fR and \fBmkfifoat()\fR mark for update
the \fBst_atime\fR, \fBst_ctime\fR, and \fBst_mtime\fR fields of the file. Also,
the \fBst_ctime\fR and \fBst_mtime\fR fields of the directory that contains the
new entry are marked for update.
.SH RETURN VALUES
Upon successful completion, \fB0\fR is returned. Otherwise, \fB\(mi1\fR is
returned and \fBerrno\fR is set to indicate the error.
.SH ERRORS
The \fBmkfifo()\fR and \fBmkfifoat()\fR functions will fail if:
.sp
.ne 2
.na
\fB\fBEACCES\fR\fR
.ad
.RS 16n
A component of the path prefix denies search permission, or write permission is
denied on the parent directory of the FIFO to be created.
.RE
.sp
.ne 2
.na
\fB\fBEEXIST\fR\fR
.ad
.RS 16n
The named file already exists.
.RE
.sp
.ne 2
.na
\fB\fBELOOP\fR\fR
.ad
.RS 16n
A loop exists in symbolic links encountered during resolution of the \fIpath\fR
argument.
.RE
.sp
.ne 2
.na
\fB\fBENAMETOOLONG\fR\fR
.ad
.RS 16n
The length of the \fIpath\fR argument exceeds {\fBPATH_MAX\fR} or a pathname
component is longer than {\fBNAME_MAX\fR}.
.RE
.sp
.ne 2
.na
\fB\fBENOENT\fR\fR
.ad
.RS 16n
A component of the path prefix specified by \fIpath\fR does not name an
existing directory or \fIpath\fR is an empty string.
.RE
.sp
.ne 2
.na
\fB\fBENOSPC\fR\fR
.ad
.RS 16n
The directory that would contain the new file cannot be extended or the file
system is out of file-allocation resources.
.RE
.sp
.ne 2
.na
\fB\fBENOTDIR\fR\fR
.ad
.RS 16n
A component of the path prefix is not a directory. For \fBmkfifoat()\fR,
\fIpath\fR is a relative path and \fIfd\fR is a valid file descriptor which is
not a directory.
.RE
.sp
.ne 2
.na
\fB\fBEROFS\fR\fR
.ad
.RS 16n
The named file resides on a read-only file system.
.RE
.sp
.LP
The \fBmkfifoat()\fR function will fail if:
.sp
.ne 2
.na
.B EBADF
.ad
.RS 16n
The \fIpath\fR argument is a relative path and \fIfd\fR is not a valid file
descriptor or the value \fBAT_FDCWD\fR.
.RE
.sp
.LP
The \fBmkfifo()\fR function may fail if:
.sp
.ne 2
.na
\fB\fBELOOP\fR\fR
.ad
.RS 16n
Too many symbolic links were encountered in resolving \fIpath\fR.
.RE
.sp
.ne 2
.na
\fB\fBENAMETOOLONG\fR\fR
.ad
.RS 16n
The length of the \fIpath\fR argument exceeds {\fBPATH_MAX\fR} or a pathname
component is longer than {\fBNAME_MAX\fR}.
.RE
.SH EXAMPLES
\fBExample 1 \fRCreate a FIFO File
.sp
.LP
The following example demonstrates how to create a FIFO file named
\fB/home/cnd/mod_done\fR with read and write permissions for the owner and read
permissions for the group and others.
.sp
.in +2
.nf
#include <sys/types.h>
#include <sys/stat.h>
int status;
\&...
status = mkfifo("/home/cnd/mod_done", S_IWUSR | S_IRUSR |
S_IRGRP | S_IROTH);
.fi
.in -2
.SH ATTRIBUTES
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp
.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE ATTRIBUTE VALUE
_
Interface Stability Standard
_
MT-Level MT-Safe
.TE
.SH SEE ALSO
\fBmkdir\fR(1), \fBchmod\fR(2), \fBexec\fR(2), \fBmknod\fR(2), \fBumask\fR(2),
\fBstat.h\fR(3HEAD), \fBufs\fR(7FS), \fBattributes\fR(5), \fBstandards\fR(5)
|
