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
|
.\"
.\" 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) 2008, Sun Microsystems, Inc. All Rights Reserved.
.\"
.TH POSIX_FALLOCATE 3C "Jul 14, 2008"
.SH NAME
posix_fallocate \- file space control
.SH SYNOPSIS
.LP
.nf
#include <fcntl.h>
\fBint\fR \fBposix_fallocate\fR(\fBint\fR \fIfd\fR, \fBoff_t\fR \fIoffset\fR, \fBoff_t\fR \fIlen\fR);
.fi
.SH DESCRIPTION
.sp
.LP
The \fBposix_fallocate()\fR function ensures that any required storage for
regular file data starting at \fIoffset\fR and continuing for \fIlen\fR bytes
is allocated on the file system storage media. If \fBposix_fallocate()\fR
returns successfully, subsequent writes to the specified file data will not
fail due to the lack of free space on the file system storage media.
.sp
.LP
If the \fIoffset\fR+\fIlen\fR is beyond the current file size, then
\fBposix_fallocate()\fR adjusts the file size to \fIoffset\fR+\fIlen\fR.
Otherwise, the file size is not changed.
.sp
.LP
Space allocated with \fBposix_fallocate()\fR is freed by a successful call to
\fBcreat\fR(2) or \fBopen\fR(2) that truncates the size of the file. Space
allocated with \fBposix_fallocate()\fR may be freed by a successful call to
\fBftruncate\fR(3C) that reduces the file size to a size smaller than
\fIoffset\fR+\fIlen\fR.
.SH RETURN VALUES
.sp
.LP
Upon successful completion, \fBposix_fallocate()\fR returns zero. Otherwise, an
error number is returned to indicate the error.
.SH ERRORS
.sp
.LP
The \fBposix_fallocate()\fR function will fail if:
.sp
.ne 2
.na
\fB\fBEBADF\fR\fR
.ad
.RS 10n
The \fIfd\fR argument is not a valid file descriptor or references a file that
was opened without write permission.
.RE
.sp
.ne 2
.na
\fB\fBEFBIG\fR\fR
.ad
.RS 10n
The value of \fIoffset\fR+\fIlen\fR is greater than the maximum file size.
.RE
.sp
.ne 2
.na
\fB\fBEINTR\fR\fR
.ad
.RS 10n
A signal was caught during execution.
.RE
.sp
.ne 2
.na
\fB\fBEINVAL\fR\fR
.ad
.RS 10n
The \fIlen\fR argument is less than or equal to zero, or the \fIoffset\fR
argument is less than zero, or the underlying file system does not support this
operation.
.RE
.sp
.ne 2
.na
\fB\fBEIO\fR\fR
.ad
.RS 10n
An I/O error occurred while reading from or writing to a file system.
.RE
.sp
.ne 2
.na
\fB\fBENODEV\fR\fR
.ad
.RS 10n
The \fIfd\fR argument does not refer to a regular file.
.RE
.sp
.ne 2
.na
\fB\fBENOSPC\fR\fR
.ad
.RS 10n
There is insufficient free space remaining on the file system storage media.
.RE
.sp
.ne 2
.na
\fB\fBESPIPE\fR\fR
.ad
.RS 10n
The \fIfd\fR argument is associated with a pipe or FIFO.
.RE
.SH USAGE
.sp
.LP
The \fBposix_fallocate()\fR function has a transitional interface for 64-bit
file offsets. See \fBlf64\fR(7).
.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 Committed
_
MT-Level MT-Safe
_
Standard See \fBstandards\fR(7).
.TE
.SH SEE ALSO
.sp
.LP
.BR creat (2),
.BR open (2),
.BR unlink (2),
.BR ftruncate (3C),
.BR attributes (7),
.BR standards (7)
|
