/usr/share/gtk-doc/html/udisks2/udisks.8.html is in udisks2-doc 2.1.7-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 | <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>udisks: UDisks Reference Manual</title>
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
<link rel="home" href="index.html" title="UDisks Reference Manual">
<link rel="up" href="overview.html" title="Part I. Manual pages and Overview">
<link rel="prev" href="overview.html" title="Part I. Manual pages and Overview">
<link rel="next" href="udisksd.8.html" title="udisksd">
<meta name="generator" content="GTK-Doc V1.24 (XML mode)">
<link rel="stylesheet" href="style.css" type="text/css">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="5"><tr valign="middle">
<td width="100%" align="left" class="shortcuts"></td>
<td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td>
<td><a accesskey="u" href="overview.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td>
<td><a accesskey="p" href="overview.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td>
<td><a accesskey="n" href="udisksd.8.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td>
</tr></table>
<div class="refentry">
<a name="udisks.8"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle">udisks</span></h2>
<p>udisks — Disk Manager</p>
</td>
<td class="gallery_image" valign="top" align="right"></td>
</tr></table></div>
<div class="refsect1">
<a name="id-1.2.2.4"></a><h2>DESCRIPTION</h2>
<p>
udisks provides interfaces to enumerate and perform operations
on disks and storage devices. Any application (including
unprivileged ones) can access the
<a class="link" href="udisksd.8.html" title="udisksd"><span class="citerefentry"><span class="refentrytitle">udisksd</span>(8)</span></a>
daemon via the name <span class="emphasis"><em>org.freedesktop.UDisks2</em></span>
on the <a class="ulink" href="http://www.freedesktop.org/wiki/Software/dbus" target="_top">system message bus</a>.
In addition to the D-Bus API, a
library, <code class="filename">libudisks2</code> is also provided. This
library can be used from C/C++ and any high-level language with
<a class="ulink" href="https://live.gnome.org/GObjectIntrospection" target="_top">GObjectIntrospection</a>
support such as Javascript and Python.
udisks is only indirectly involved in what devices and objects
are shown in the user interface. See these
<a class="ulink" href="http://git.gnome.org/browse/gvfs/tree/monitor/udisks2/what-is-shown.txt" target="_top">notes</a>
for what is shown in GNOME 3.
</p>
</div>
<div class="refsect1">
<a name="id-1.2.2.5"></a><h2>ACCESS CONTROL</h2>
<p>
By default, logged-in users in active log-in sessions are
permitted to perform operations (for example, mounting,
unlocking or modifying) on devices attached to the seat their
session is on. Access-control is fine-grained and based on
<span class="citerefentry"><span class="refentrytitle">polkit</span>(8)</span>,
see the <span class="quote">“<span class="quote"><a class="link" href="udisks-polkit-actions.html" title="Authorization Checks">Authorization
Checks</a></span>”</span> chapter in the udisks documentation for
more information.
Note that the <code class="literal">x-udisks-auth</code> option can be
used in the <code class="filename">/etc/fstab</code> and
<code class="filename">/etc/crypttab</code> files to specify that
additional authorization is required to mount resp. unlock the
device (typically requiring the user to authenticate as an
administrator).
</p>
</div>
<div class="refsect1">
<a name="id-1.2.2.6"></a><h2>DRIVE CONFIGURATION</h2>
<p>
At start-up and when a drive is connected,
<a class="link" href="udisksd.8.html" title="udisksd"><span class="citerefentry"><span class="refentrytitle">udisksd</span>(8)</span></a>
will apply configuration stored in the file
<code class="filename">/etc/udisks2/IDENTIFIER.conf</code>
where <span class="emphasis"><em>IDENTIFIER</em></span> is the value of the
<a class="link" href="gdbus-org.freedesktop.UDisks2.Drive.html#gdbus-property-org-freedesktop-UDisks2-Drive.Id" title='The "Id" property'>Drive:Id</a>
property for the drive. If the file changes on disk its new
contents will also be applied to the drive.
Typically, users or administrators will never need to edit drive
configuration files as they are effectively managed through
graphical applications such as
<span class="citerefentry"><span class="refentrytitle">gnome-disks</span>(1)</span>.
Manually editing configuration files is however supported — the file
format is a simple <span class="emphasis"><em>.ini-like format</em></span>
(see the
<a class="ulink" href="http://freedesktop.org/wiki/Specifications/desktop-entry-spec" target="_top">Desktop Entry Specification</a>
for the exact syntax). New groups and keys may
be added in the future.
</p>
<div class="refsect2">
<a name="id-1.2.2.6.3"></a><h3>ATA group</h3>
<p>
The <code class="literal">ATA</code> group is for settings that apply to
drives using the ATA command-set. The following keys are
supported:
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><code class="option">StandbyTimeout</code></span></p></td>
<td><p>
The standby timeout. A value of zero means "timeouts
are disabled": the device will not automatically enter
standby mode. Values from 1 to 240 specify multiples of
5 seconds, yielding timeouts from 5 seconds to 20
minutes. Values from 241 to 251 specify from 1 to 11
units of 30 minutes, yielding timeouts from 30 minutes
to 5.5 hours. A value of 252 signifies a timeout of 21
minutes. A value of 253 sets a vendor-defined timeout
period between 8 and 12 hours, and the value 254 is
reserved. 255 is interpreted as 21 minutes plus 15
seconds. Note that some older drives may have very
different interpretations of these values.
This is similar to the <code class="option">-S</code> option in
<span class="citerefentry"><span class="refentrytitle">hdparm</span>(8)</span>.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">APMLevel</code></span></p></td>
<td><p>
The Advanced Power Management level. A low value means
aggressive power management and a high value means
better performance. Possible settings range from values
1 through 127 (which permit spin-down), and values 128
through 254 (which do not permit spin-down). The
highest degree of power management is attained with a
setting of 1, and the highest I/O performance with a
setting of 254. A value of 255 can be used to disable
Advanced Power Management altogether on the drive (not
all drives support disabling it, but most do).
This is similar to the <code class="option">-B</code> option in
<span class="citerefentry"><span class="refentrytitle">hdparm</span>(8)</span>.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">AAMLevel</code></span></p></td>
<td><p>
The Automatic Acoustic Management level. Most modern
harddisk drives have the ability to speed down the head
movements to reduce their noise output. The possible
values are between 0 and 254. 128 is the most quiet (and
therefore slowest) setting and 254 the fastest (and
loudest). Some drives have only two levels (quiet /
fast), while others may have different levels between
128 and 254. At the moment, most drives only support 3
options, off, quiet, and fast. These have been assigned
the values 0, 128, and 254 at present, respectively, but
integer space has been incorporated for future
expansion, should this change.
This is similar to the <code class="option">-M</code> option in
<span class="citerefentry"><span class="refentrytitle">hdparm</span>(8)</span>.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">WriteCacheEnabled</code></span></p></td>
<td><p>
A boolean specifying whether to enable or disable the
Write Cache. Valid values for this key are
<span class="quote">“<span class="quote">true</span>”</span> and <span class="quote">“<span class="quote">false</span>”</span>. This is
similar to the <code class="option">-W</code> option in
<span class="citerefentry"><span class="refentrytitle">hdparm</span>(8)</span>.
This key was added in 2.1.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">ReadLookaheadEnabled</code></span></p></td>
<td><p>
A boolean specifying whether to enable or disable the
Read Look-ahead. Valid values for this key are
<span class="quote">“<span class="quote">true</span>”</span> and <span class="quote">“<span class="quote">false</span>”</span>. This is
similar to the <code class="option">-A</code> option in
<span class="citerefentry"><span class="refentrytitle">hdparm</span>(8)</span>.
This key was added in 2.1.7.
</p></td>
</tr>
</tbody>
</table></div>
</div>
</div>
<div class="refsect1">
<a name="id-1.2.2.7"></a><h2>DEVICE INFORMATION</h2>
<p>
udisks relies on recent versions of
<span class="citerefentry"><span class="refentrytitle">udev</span>(7)</span>
and the Linux kernel. Influential device properties in the udev
database include:
</p>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term"><code class="option">UDISKS_SYSTEM</code></span></p></td>
<td><p>
If set, this overrides the value of the
<a class="link" href="gdbus-org.freedesktop.UDisks2.Block.html#gdbus-property-org-freedesktop-UDisks2-Block.HintSystem" title='The "HintSystem" property'>HintSystem</a> property.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">UDISKS_IGNORE</code></span></p></td>
<td><p>
If set, this overrides the value of the
<a class="link" href="gdbus-org.freedesktop.UDisks2.Block.html#gdbus-property-org-freedesktop-UDisks2-Block.HintIgnore" title='The "HintIgnore" property'>HintIgnore</a> property.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">UDISKS_AUTO</code></span></p></td>
<td><p>
If set, this overrides the value of the
<a class="link" href="gdbus-org.freedesktop.UDisks2.Block.html#gdbus-property-org-freedesktop-UDisks2-Block.HintAuto" title='The "HintAuto" property'>HintAuto</a> property.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">UDISKS_CAN_POWER_OFF</code></span></p></td>
<td><p>
If set, this overrides the value of the
<a class="link" href="gdbus-org.freedesktop.UDisks2.Drive.html#gdbus-property-org-freedesktop-UDisks2-Drive.CanPowerOff" title='The "CanPowerOff" property'>CanPowerOff</a> property.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">UDISKS_NAME</code></span></p></td>
<td><p>
The name to use for the device when presenting it in an user interface.
This corresponds to the
<a class="link" href="gdbus-org.freedesktop.UDisks2.Block.html#gdbus-property-org-freedesktop-UDisks2-Block.HintName" title='The "HintName" property'>HintName</a> property.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">UDISKS_ICON_NAME</code></span></p></td>
<td><p>
The icon to use for the device when presenting it in an user interface. If
set, the name must adhere to the
<a class="ulink" href="http://www.freedesktop.org/wiki/Specifications/icon-theme-spec" target="_top">freedesktop.org icon theme specification</a>.
This corresponds to the
<a class="link" href="gdbus-org.freedesktop.UDisks2.Block.html#gdbus-property-org-freedesktop-UDisks2-Block.HintIconName" title='The "HintIconName" property'>HintIconName</a> property.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">UDISKS_SYMBOLIC_ICON_NAME</code></span></p></td>
<td><p>
The icon to use for the device when presenting it in an user interface using a symbolic icon. If
set, the name must adhere to the
<a class="ulink" href="http://www.freedesktop.org/wiki/Specifications/icon-theme-spec" target="_top">freedesktop.org icon theme specification</a>.
This corresponds to the
<a class="link" href="gdbus-org.freedesktop.UDisks2.Block.html#gdbus-property-org-freedesktop-UDisks2-Block.HintIconName" title='The "HintIconName" property'>HintSymbolicIconName</a> property.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">UDISKS_FILESYSTEM_SHARED</code></span></p></td>
<td><p>
If set to 1, the filesystem on the device will be mounted in a shared directory (e.g. <code class="filename">/media/VolumeName</code>) instead of a private directory (e.g. <code class="filename">/run/media/$USER/VolumeName</code>) when the <a class="link" href="gdbus-org.freedesktop.UDisks2.Filesystem.html#gdbus-method-org-freedesktop-UDisks2-Filesystem.Mount" title="The Mount() method">Filesystem.Mount()</a> method is handled.
</p></td>
</tr>
<tr>
<td><p><span class="term"><code class="option">ID_SEAT</code></span></p></td>
<td><p>
The physical seat the device is attached to. If unset or
set to the empty string, <span class="quote">“<span class="quote">seat0</span>”</span> (the first
seat) is assumed.
</p></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="id-1.2.2.8"></a><h2>API STABILITY</h2>
<p>
udisks guarantees a stable D-Bus API within the same major
version and this guarantee also extends to the client-side
library <code class="filename">libudisks2</code>. Additionally, several
major versions of udisks can be installed and operate at the
same time although interoperability may be limited - for
example, a device mounted using the udisks N.x API may require
additional authorization if attempting to unmount it through the
the (N-1).x API.
</p>
<p>
The udisks developers do not anticipate breaking API but does
reserve the right to do so and if it happens, promises to bump
the major version and ensure the new major version of udisks is
parallel-installable with any older major version. However, note
that programs, man pages and other artifacts may change name
(for example, adopt a <span class="quote">“<span class="quote">2</span>”</span> suffix) to make room for
the next major version. Therefore, applications can not rely on
tools like e.g.
<a class="link" href="udisksctl.1.html" title="udisksctl"><span class="citerefentry"><span class="refentrytitle">udisksctl</span>(1)</span></a>
to be available. Additionally, there is no guarantee that the
options, command-line switches etc. of command-line tools or
similar will remain stable.
</p>
<p>
Instead, applications should only use the D-Bus API, the
<code class="filename">libudisks2</code> library or tools such as
<span class="citerefentry"><span class="refentrytitle">dbus-send</span>(1)</span>
or
<span class="citerefentry"><span class="refentrytitle">gdbus</span>(1)</span>
to interact with
<a class="link" href="udisksd.8.html" title="udisksd"><span class="citerefentry"><span class="refentrytitle">udisksd</span>(8)</span></a>.
</p>
</div>
<div class="refsect1">
<a name="id-1.2.2.9"></a><h2>AUDIENCE</h2>
<p>
The intended audience of udisks include operating system
developers working on the higher-level parts of the operating
system, for example the desktop shell (such as <a class="ulink" href="http://www.gnome.org" target="_top">GNOME</a>) and disk management
applications (e.g. GNOME's <a class="ulink" href="https://live.gnome.org/Design/Apps/Disks" target="_top">Disks</a>
application). Software on this level typically depend on a
specific (major) version of udisks and may even have support for
previous versions of udisks or alternative interfaces performing
the same role as udisks.
</p>
<p>
While udisks indeed provides a stable API and a clear upgrade
path, it may not be an appropriate dependency for third party
applications. For example, if the operating system switches to
udisks version N.x and an application is still using the udisks
(N-1).x API, the application will not work unless udisks (N-1).x
is installed. While this situation is still workable (since both
udisks N.x and udisks (N-1).x can be installed) it may not be
desirable to ask the user to install the old version - in fact,
the operating system vendor may not even provide a packaged
version of the old version. Hence, if an application does not
want to tie itself to a specific version of the operating
system, it should not use udisks.
</p>
<p>
Viable alternatives to udisks are APIs that are guaranteed to be
around for longer time-frames, including:
</p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>
Low-level APIs and commands such as e.g.
<a class="ulink" href="http://en.wikipedia.org/wiki/Sysfs" target="_top">sysfs</a>,
<a class="ulink" href="http://www.freedesktop.org/software/systemd/libudev/" target="_top">libudev</a>,
<a class="ulink" href="http://www.kernel.org/doc/Documentation/filesystems/proc.txt" target="_top">/proc/self/mountinfo</a> and
<a class="ulink" href="http://en.wikipedia.org/wiki/Util-linux" target="_top">util-linux</a>.
</p></li>
<li class="listitem"><p>
High-level APIs such as <a class="ulink" href="http://developer.gnome.org/gio/stable/volume_mon.html" target="_top">GVolumeMonitor</a>.
</p></li>
</ul></div>
<p>
In particular, for desktop applications it is a much better idea
to use something like GVolumeMonitor since it will make the
application show the same devices as the desktop shell
(e.g. file manager, file chooser and so on) is showing.
</p>
</div>
<div class="refsect1">
<a name="id-1.2.2.10"></a><h2>AUTHOR</h2>
<p>
Written by David Zeuthen
<code class="email"><<a class="email" href="mailto:zeuthen@gmail.com">zeuthen@gmail.com</a>></code> with a lot of help
from many others.
</p>
</div>
<div class="refsect1">
<a name="id-1.2.2.11"></a><h2>BUGS</h2>
<p>
Please send bug reports to either the distribution bug tracker
or the upstream bug tracker at
<a class="ulink" href="http://bugs.freedesktop.org/enter_bug.cgi?product=udisks" target="_top">http://bugs.freedesktop.org/enter_bug.cgi?product=udisks</a>.
</p>
</div>
<div class="refsect1">
<a name="id-1.2.2.12"></a><h2>SEE ALSO</h2>
<p>
<span class="citerefentry"><span class="refentrytitle">udev</span>(7)</span>,
<span class="citerefentry"><span class="refentrytitle">polkit</span>(8)</span>,
<a class="link" href="udisksd.8.html" title="udisksd"><span class="citerefentry"><span class="refentrytitle">udisksd</span>(8)</span></a>,
<a class="link" href="udisksctl.1.html" title="udisksctl"><span class="citerefentry"><span class="refentrytitle">udisksctl</span>(1)</span></a>,
<span class="citerefentry"><span class="refentrytitle">umount.udisks2</span>(8)</span>,
<span class="citerefentry"><span class="refentrytitle">gnome-disks</span>(1)</span>
</p>
</div>
</div>
<div class="footer">
<hr>Generated by GTK-Doc V1.24</div>
</body>
</html>
|