1 .\" Copyright (c) 1980, 1989, 1993
2 .\" The Regents of the University of California. All rights reserved.
4 .\" Redistribution and use in source and binary forms, with or without
5 .\" modification, are permitted provided that the following conditions
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 .\" 3. All advertising materials mentioning features or use of this software
13 .\" must display the following acknowledgement:
14 .\" This product includes software developed by the University of
15 .\" California, Berkeley and its contributors.
16 .\" 4. Neither the name of the University nor the names of its contributors
17 .\" may be used to endorse or promote products derived from this software
18 .\" without specific prior written permission.
20 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 .\" @(#)mount.2 8.3 (Berkeley) 5/24/95
41 .Nd mount or dismount a filesystem
48 .Fn mount "const char *type" "const char *dir" "int flags" "void *data"
50 .Fn unmount "const char *dir" "int flags"
55 a filesystem object onto the system file tree
60 describes the filesystem object to be mounted.
63 tells the kernel how to interpret
68 The contents of the filesystem
69 become available through the new mount point
74 of a successful mount are swept under the carpet so to speak, and
75 are unavailable until the filesystem is unmounted.
80 suppress default semantics which affect filesystem access.
81 .Bl -tag -width MNT_SYNCHRONOUS
83 The filesystem should be treated as read-only;
84 Even the super-user may not write on it.
85 Specifying MNT_UPDATE without this option will upgrade
86 a read-only filesystem to read/write.
88 Do not allow files to be executed from the filesystem.
90 Do not honor setuid or setgid bits on files when executing them.
92 Disable update of file access times.
94 Do not interpret special files on the filesystem.
96 Directories with the SUID bit set chown new files to their own owner.
97 .It Dv MNT_SYNCHRONOUS
98 All I/O to the filesystem should be done synchronously.
100 All I/O to the filesystem should be done asynchronously.
102 Force a read-write mount even if the filesystem appears to be unclean.
104 .It Dv MNT_NOCLUSTERR
105 Disable read clustering.
106 .It Dv MNT_NOCLUSTERW
107 Disable write clustering.
112 indicates that the mount command is being applied
113 to an already mounted filesystem.
114 This allows the mount flags to be changed without requiring
115 that the filesystem be unmounted and remounted.
116 Some filesystems may not allow all flags to be changed.
118 many filesystems will not allow a change from read-write to read-only.
122 causes the vfs subsystem to update its data structures pertaining to
123 the specified already mounted filesystem.
127 argument names the filesystem.
128 The types of filesystems known to the system can be obtained with
132 is a pointer to a structure that contains the type
133 specific arguments to mount.
134 The format for these argument structures is described in the
135 manual page for each filesystem.
136 By convention filesystem manual pages are named
137 by prefixing ``mount_'' to the name of the filesystem as returned by
141 filesystem is described by the
147 function call disassociates the filesystem from the specified
155 to specify that the filesystem should be forcibly unmounted or made read-only
156 (if MNT_UPDATE and MNT_RDONLY are also specified)
157 even if files are still active.
158 Active special devices continue to work,
159 but any further accesses to any other active files result in errors
160 even if the filesystem is later remounted.
164 option requires the SUIDDIR option to have been compiled into the kernel
170 pages for more information.
176 function will fail when one of the following occurs:
179 The caller is not the super-user.
180 .It Bq Er ENAMETOOLONG
181 A component of a pathname exceeded 255 characters,
182 or the entire length of a path name exceeded 1023 characters.
184 Too many symbolic links were encountered in translating a pathname.
197 Another process currently holds a reference to
201 points outside the process's allocated address space.
204 The following errors can occur for a
209 A component of ufs_args
214 is not a block device.
216 The major device number of
218 is out of range (this indicates no device driver exists
219 for the associated hardware).
224 No space remains in the mount table.
226 The super block for the filesystem had a bad magic
227 number or an out of range block size.
229 Not enough memory was available to read the cylinder
230 group information for the filesystem.
232 An I/O error occurred while reading the super block or
233 cylinder group information.
236 points outside the process's allocated address space.
239 The following errors can occur for a
245 timed out trying to contact the server.
247 Some part of the information described by nfs_args
248 points outside the process's allocated address space.
253 function may fail with one of the following errors:
256 The caller is not the super-user.
258 A component of the path is not a directory.
259 .It Bq Er ENAMETOOLONG
260 A component of a pathname exceeded 255 characters,
261 or an entire path name exceeded 1023 characters.
263 Too many symbolic links were encountered in translating the pathname.
265 The requested directory is not in the mount table.
267 A process is holding a reference to a file located
270 An I/O error occurred while writing cached filesystem information.
273 points outside the process's allocated address space.
278 mount can also fail if the maximum number of filesystems are currently
285 Some of the error codes need translation to more obvious messages.
290 function calls appeared in