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<div class='body'>
<!--
- "$Id: api-filter.header 7285 2008-02-01 23:57:39Z mike $"
+ "$Id: api-filter.header 8627 2009-05-13 21:39:17Z mike $"
Filter and backend programming header for the Common UNIX Printing System
(CUPS).
- Copyright 2008 by Apple Inc.
+ Copyright 2008-2009 by Apple Inc.
These coded instructions, statements, and computer programs are the
property of Apple Inc. and are protected by Federal copyright
file is missing or damaged, see the license at "http://www.cups.org/".
-->
-<h1 class="title">Filter and Backend Programming</h1>
+<h1 class='title'>Filter and Backend Programming</h1>
<div class='summary'><table summary='General Information'>
<thead>
<tr>
<th>Headers</th>
<th>cups/backend.h<br>
- cups/sidechannel.h<br>
- cups/snmp.h</th>
+ cups/sidechannel.h</th>
</tr>
</thead>
<tbody>
<td>Programming: <a href='api-overview.html' target='_top'>Introduction to CUPS Programming</a><br>
Programming: <a href='api-cups.html' target='_top'>CUPS API</a><br>
Programming: <a href='api-ppd.html' target='_top'>PPD API</a><br>
- Programming: <a href='api-raster.html' target='_top'>Raster API</a></td>
+ Programming: <a href='api-raster.html' target='_top'>Raster API</a><br>
+ Specifications: <a href='spec-design' target='_top'>CUPS Design Description</a></td>
</tr>
</tbody>
</table></div>
<h2 class="title">Contents</h2>
<ul class="contents">
-</li>
+<ul class="subcontents">
<li><a href="#OVERVIEW">Overview</a><ul class="subcontents">
<li><a href="#SECURITY">Security Considerations</a></li>
+<li><a href="#PERMISSIONS">File Permissions</a></li>
<li><a href="#TEMPFILES">Temporary Files</a></li>
<li><a href="#COPIES">Copy Generation</a></li>
<li><a href="#EXITCODES">Exit Codes</a></li>
<li><a href="#cupsBackChannelRead" title="Read data from the backchannel.">cupsBackChannelRead</a></li>
<li><a href="#cupsBackChannelWrite" title="Write data to the backchannel.">cupsBackChannelWrite</a></li>
<li><a href="#cupsBackendDeviceURI" title="Get the device URI for a backend.">cupsBackendDeviceURI</a></li>
+<li><a href="#cupsBackendReport" title="Write a device line from a backend.">cupsBackendReport</a></li>
<li><a href="#cupsSideChannelDoRequest" title="Send a side-channel command to a backend and wait for a response.">cupsSideChannelDoRequest</a></li>
<li><a href="#cupsSideChannelRead" title="Read a side-channel message.">cupsSideChannelRead</a></li>
<li><a href="#cupsSideChannelSNMPGet" title="Query a SNMP OID's value.">cupsSideChannelSNMPGet</a></li>
<li><a href="#cupsSideChannelSNMPWalk" title="Query multiple SNMP OID values.">cupsSideChannelSNMPWalk</a></li>
<li><a href="#cupsSideChannelWrite" title="Write a side-channel message.">cupsSideChannelWrite</a></li>
-</ul>
+</ul></li>
<li><a href="#TYPES">Data Types</a><ul class="code">
<li><a href="#cups_backend_t" title="Backend exit codes">cups_backend_t</a></li>
<li><a href="#cups_sc_bidi_t" title="Bidirectional capabilities">cups_sc_bidi_t</a></li>
</ul></li>
<li><a href="#ENUMERATIONS">Constants</a><ul class="code">
<li><a href="#cups_backend_e" title="Backend exit codes">cups_backend_e</a></li>
- <li><a href="#cups_sc_bidi_e" title="Bidirectional capabilities">cups_sc_bidi_e</a></li>
+ <li><a href="#cups_sc_bidi_e" title="Bidirectional capability values">cups_sc_bidi_e</a></li>
<li><a href="#cups_sc_command_e" title="Request command codes">cups_sc_command_e</a></li>
<li><a href="#cups_sc_state_e" title="Printer state bits">cups_sc_state_e</a></li>
<li><a href="#cups_sc_status_e" title="Response status codes">cups_sc_status_e</a></li>
</ul></li>
-</ul>
<!--
- "$Id: api-filter.shtml 7502 2008-04-28 21:30:12Z mike $"
+ "$Id: api-filter.shtml 7962 2008-09-18 17:31:33Z mike $"
Filter and backend programming introduction for the Common UNIX Printing
System (CUPS).
- Copyright 2007-2008 by Apple Inc.
+ Copyright 2007-2009 by Apple Inc.
Copyright 1997-2006 by Easy Software Products, all rights reserved.
These coded instructions, statements, and computer programs are the
<h2 class='title'><a name="OVERVIEW">Overview</a></h2>
-<p>Filters, printer drivers, port monitors, and backends use a common interface
-for processing print jobs and communicating status information to the scheduler.
-Each filter is run with a standard set of command-line arguments:<p>
+<p>Filters (which include printer drivers and port monitors) and backends
+are used to convert job files to a printable format and send that data to the
+printer itself. All of these programs use a common interface for processing
+print jobs and communicating status information to the scheduler. Each is run
+with a standard set of command-line arguments:<p>
<dl class="code">
<dd>The options that were provided when the job was submitted</dd>
<dt>argv[6]</dt>
- <dd>The file to print (first filter only)</dd>
+ <dd>The file to print (first program only)</dd>
</dl>
<p>The scheduler runs one or more of these programs to print any given job. The
output. The backend is the last filter in the chain and writes to the
device.</p>
+<p>Filters are always run as a non-privileged user, typically "lp", with no
+connection to the user's desktop. Backends are run either as a non-privileged
+user or as root if the file permissions do not allow user or group execution.
+The <a href="#PERMISSIONS">file permissions</a> section talks about this in
+more detail.</p>
+
<h3><a name="SECURITY">Security Considerations</a></h3>
<p>It is always important to use security programming practices. Filters and
used by the filter since that can lead to an unauthorized disclosure of
information. <em>Always</em> treat input as suspect and validate it!</p>
-<p>If you are developing a backend that runs as root, make sure to check for
+<p>If you are developing a backend that runs as root , make sure to check for
potential buffer overflows, integer under/overflow conditions, and file
accesses since these can lead to privilege escalations. When writing files,
always validate the file path and <em>never</em> allow a user to determine
directory to write to.</p>
<p>In addition, some operating systems provide additional security mechanisms
-that further limit file system access, even for backends running as root. On
+that further limit file system access, even for backends running as root. On
Mac OS X, for example, no backend may write to a user's home directory.</p>
</blockquote>
+<h3><a name="PERMISSIONS">File Permissions</a></h3>
+
+<p>For security reasons, CUPS will only run filters and backends that are owned
+by root and do not have world write permissions. The recommended permissions for
+filters and backends are 0555 - read and execute but no write. Backends that
+must run as root should use permissions of 0500 - read and execute by root, no
+access for other users. Write permissions can be enabled for the root user
+only.</p>
+
+<p>To avoid a warning message, the directory containing your filter(s) must also
+be owned by root and have world write disabled - permissions of 0755 or 0555 are
+strongly encouraged.</p>
+
<h3><a name="TEMPFILES">Temporary Files</a></h3>
<p>Temporary files should be created in the directory specified by the
<h3><a name="ENVIRONMENT">Environment Variables</a></h3>
-<p>The following environment variables are defined by the printing system:</p>
+<p>The following environment variables are defined by the printing system
+when running print filters and backends:</p>
<dl class="code">
application/postscript).</dd>
<dt>CUPS_CACHEDIR</dt>
- <dd>The directory where cache files can be stored.</dd>
+ <dd>The directory where cache files can be stored. Cache files can be
+ used to retain information between jobs or files in a job.</dd>
<dt>CUPS_DATADIR</dt>
- <dd>The directory where data files can be found.</dd>
+ <dd>The directory where (read-only) CUPS data files can be found.</dd>
+
+ <dt>CUPS_FILETYPE</dt>
+ <dd>The type of file being printed: "job-sheet" for a banner page and
+ "document" for a regular print file.</dd>
<dt>CUPS_SERVERROOT</dt>
<dd>The root directory of the server.</dd>
file for this printer.</dd>
<dt>PRINTER</dt>
- <dd>The name of the printer.</dd>
+ <dd>The queue name of the class or printer.</dd>
<dt>RIP_CACHE</dt>
<dd>The recommended amount of memory to use for Raster Image
Processors (RIPs).</dd>
+ <dt>TMPDIR</dt>
+ <dd>The directory where temporary files should be created.</dd>
+
</dl>
<h3><a name="MESSAGES">Communicating with the Scheduler</a></h3>
-<p>Filters and backends communicate wih the scheduler by writing messages
-to the standard error file. For example, the following code sets the current
-printer state message to "Printing page 5":</p>
+<p>Filters and backends communicate with the scheduler by writing messages
+to the standard error file. The scheduler reads messages from all filters in
+a job and processes the message based on its prefix. For example, the following
+code sets the current printer state message to "Printing page 5":</p>
<pre class="example">
int page = 5;
<dt>ATTR: attribute=value [attribute=value]</dt>
<dd>Sets the named printer or job attribute(s). Typically this is used
to set the <code>marker-colors</code>, <code>marker-levels</code>,
- <code>marker-names</code>, <code>marker-types</code>,
- <code>printer-alert</code>, and <code>printer-alert-description</code>
- printer attributes.</dd>
+ <code>marker-message</code>, <code>marker-names</code>,
+ <code>marker-types</code>, <code>printer-alert</code>, and
+ <code>printer-alert-description</code> printer attributes. Standard
+ <code>marker-types</code> values are listed in <a href='#TABLE1'>Table
+ 1</a>.</dd>
<dt>CRIT: message</dt>
<dd>Sets the printer-state-message attribute and adds the specified
<dt>ERROR: message</dt>
<dd>Sets the printer-state-message attribute and adds the specified
- message to the current error log file using the "error" log level.</dd>
+ message to the current error log file using the "error" log level.
+ Use "ERROR:" messages for non-persistent processing errors.</dd>
<dt>INFO: message</dt>
<dd>Sets the printer-state-message attribute. If the current log level
<dt>STATE: + printer-state-reason [printer-state-reason ...]</dt>
<dt>STATE: - printer-state-reason [printer-state-reason ...]</dt>
<dd>Sets, adds, or removes printer-state-reason keywords to the
- current queue. Typically this is used to indicate media, ink, and
- toner conditions on a printer.</dd>
+ current queue. Typically this is used to indicate persistent media,
+ ink, toner, and configuration conditions or errors on a printer.
+ <a href='#TABLE2'>Table 2</a> lists the standard state keywords -
+ use vendor-prefixed ("com.acme.foo") keywords for custom states.</dd>
<dt>WARNING: message</dt>
<dd>Sets the printer-state-message attribute and adds the specified
<p>Messages without one of these prefixes are treated as if they began with
the "DEBUG:" prefix string.</p>
+
+<div class='table'><table width='80%' summary='Table 1: Standard marker-types Values'>
+<caption>Table 1: <a name='TABLE1'>Standard marker-types Values</a></caption>
+<thead>
+<tr>
+ <th>marker-type</th>
+ <th>Description</th>
+</tr>
+</thead>
+<tbody>
+<tr>
+ <td>developer</td>
+ <td>Developer unit</td>
+</tr>
+<tr>
+ <td>fuser</td>
+ <td>Fuser unit</td>
+</tr>
+<tr>
+ <td>fuserCleaningPad</td>
+ <td>Fuser cleaning pad</td>
+</tr>
+<tr>
+ <td>fuserOil</td>
+ <td>Fuser oil</td>
+</tr>
+<tr>
+ <td>ink</td>
+ <td>Ink supply</td>
+</tr>
+<tr>
+ <td>opc</td>
+ <td>Photo conductor</td>
+</tr>
+<tr>
+ <td>solidWax</td>
+ <td>Wax supply</td>
+</tr>
+<tr>
+ <td>staples</td>
+ <td>Staple supply</td>
+</tr>
+<tr>
+ <td>toner</td>
+ <td>Toner supply</td>
+</tr>
+<tr>
+ <td>transferUnit</td>
+ <td>Transfer unit</td>
+</tr>
+<tr>
+ <td>wasteInk</td>
+ <td>Waste ink tank</td>
+</tr>
+<tr>
+ <td>wasteToner</td>
+ <td>Waste toner tank</td>
+</tr>
+<tr>
+ <td>wasteWax</td>
+ <td>Waste wax tank</td>
+</tr>
+</tbody>
+</table></div>
+
+<br>
+
+<div class='table'><table width='80%' summary='Table 2: Standard State Keywords'>
+<caption>Table 2: <a name='TABLE2'>Standard State Keywords</a></caption>
+<thead>
+<tr>
+ <th>Keyword</th>
+ <th>Description</th>
+</tr>
+</thead>
+<tbody>
+<tr>
+ <td>connecting-to-device</td>
+ <td>Connecting to printer but not printing yet</td>
+</tr>
+<tr>
+ <td>cover-open</td>
+ <td>A cover is open on the printer</td>
+</tr>
+<tr>
+ <td>input-tray-missing</td>
+ <td>An input tray is missing from the printer</td>
+</tr>
+<tr>
+ <td>marker-supply-empty</td>
+ <td>Out of ink</td>
+</tr>
+<tr>
+ <td>marker-supply-low</td>
+ <td>Low on ink</td>
+</tr>
+<tr>
+ <td>marker-waste-almost-full</td>
+ <td>Waste tank almost full</td>
+</tr>
+<tr>
+ <td>marker-waste-full</td>
+ <td>Waste tank full</td>
+</tr>
+<tr>
+ <td>media-empty</td>
+ <td>Out of media</td>
+</tr>
+<tr>
+ <td>media-jam</td>
+ <td>Media is jammed in the printer</td>
+</tr>
+<tr>
+ <td>media-low</td>
+ <td>Low on media</td>
+</tr>
+<tr>
+ <td>paused</td>
+ <td>Stop the printer</td>
+</tr>
+<tr>
+ <td>timed-out</td>
+ <td>Unable to connect to printer</td>
+</tr>
+<tr>
+ <td>toner-empty</td>
+ <td>Out of toner</td>
+</tr>
+<tr>
+ <td>toner-low</td>
+ <td>Low on toner</td>
+</tr>
+</tbody>
+</table></div>
+
<h3><a name="COMMUNICATING_BACKEND">Communicating with the Backend</a></h3>
<p>Filters can communicate with the backend via the
bytes = cupsBackChannelRead(buffer, sizeof(buffer), 0.0);
</pre>
-The
+<p>Filters can also use <code>select()</code> or <code>poll()</code> on the
+back-channel file descriptor (3 or <code>CUPS_BC_FD</code>) to read data only
+when it is available.</p>
+
+<p>The
<a href="#cupsSideChannelDoRequest"><code>cupsSideChannelDoRequest</code></a>
function allows you to get out-of-band status information and do synchronization
with the device. For example, the following code gets the current IEEE-1284
int datalen;
<a href="#cups_sc_status_t">cups_sc_status_t</a> status;
-/* Tell cupsSideChannelDoRequest() how big our buffer is, less 1 byte for nul-termination... */
+/* Tell cupsSideChannelDoRequest() how big our buffer is, less 1 byte for
+ nul-termination... */
datalen = sizeof(data) - 1;
/* Get the IEEE-1284 device ID, waiting for up to 1 second */
char buffer[8192];
ssize_t bytes;
+/* Obtain data from printer/device */
+...
+
/* Use a timeout of 1.0 seconds to give filters a chance to read */
cupsBackChannelWrite(buffer, bytes, 1.0);
</pre>
<a href="#cupsSideChannelSNMPWalk">cupsSNMPSideChannelWalk</a>(".1.3.6.1.2.1.43", 5.0, my_callback, my_data);
</pre>
<h2 class="title"><a name="FUNCTIONS">Functions</a></h2>
-<h3 class="function"><span class="info"> CUPS 1.2 </span><a name="cupsBackChannelRead">cupsBackChannelRead</a></h3>
+<h3 class="function"><span class="info"> CUPS 1.2
/Mac OS X 10.5 </span><a name="cupsBackChannelRead">cupsBackChannelRead</a></h3>
<p class="description">Read data from the backchannel.</p>
<p class="code">
ssize_t cupsBackChannelRead (<br>
<h4 class="parameters">Parameters</h4>
<dl>
<dt>buffer</dt>
-<dd class="description">Buffer to read</dd>
+<dd class="description">Buffer to read into</dd>
<dt>bytes</dt>
<dd class="description">Bytes to read</dd>
<dt>timeout</dt>
-<dd class="description">Timeout in seconds</dd>
+<dd class="description">Timeout in seconds, typically 0.0 to poll</dd>
</dl>
<h4 class="returnvalue">Return Value</h4>
<p class="description">Bytes read or -1 on error</p>
<h4 class="discussion">Discussion</h4>
-<p class="discussion">Reads up to "bytes" bytes from the backchannel. The "timeout"
-parameter controls how many seconds to wait for the data - use
-0.0 to return immediately if there is no data, -1.0 to wait
-for data indefinitely.
+<p class="discussion">Reads up to "bytes" bytes from the backchannel/backend. The "timeout"
+parameter controls how many seconds to wait for the data - use 0.0 to
+return immediately if there is no data, -1.0 to wait for data indefinitely.
</p>
-<h3 class="function"><span class="info"> CUPS 1.2 </span><a name="cupsBackChannelWrite">cupsBackChannelWrite</a></h3>
+<h3 class="function"><span class="info"> CUPS 1.2
/Mac OS X 10.5 </span><a name="cupsBackChannelWrite">cupsBackChannelWrite</a></h3>
<p class="description">Write data to the backchannel.</p>
<p class="code">
ssize_t cupsBackChannelWrite (<br>
<dt>bytes</dt>
<dd class="description">Bytes to write</dd>
<dt>timeout</dt>
-<dd class="description">Timeout in seconds</dd>
+<dd class="description">Timeout in seconds, typically 1.0</dd>
</dl>
<h4 class="returnvalue">Return Value</h4>
<p class="description">Bytes written or -1 on error</p>
<h4 class="discussion">Discussion</h4>
-<p class="discussion">Writes "bytes" bytes to the backchannel. The "timeout" parameter
+<p class="discussion">Writes "bytes" bytes to the backchannel/filter. The "timeout" parameter
controls how many seconds to wait for the data to be written - use
0.0 to return immediately if the data cannot be written, -1.0 to wait
indefinitely.
</p>
-<h3 class="function"><a name="cupsBackendDeviceURI">cupsBackendDeviceURI</a></h3>
+<h3 class="function"><span class="info"> CUPS 1.2/Mac OS X 10.5 </span><a name="cupsBackendDeviceURI">cupsBackendDeviceURI</a></h3>
<p class="description">Get the device URI for a backend.</p>
<p class="code">
const char *cupsBackendDeviceURI (<br>
<p class="discussion">The "argv" argument is the argv argument passed to main(). This
function returns the device URI passed in the DEVICE_URI environment
variable or the device URI passed in argv[0], whichever is found
-first.</p>
-<h3 class="function"><span class="info"> CUPS 1.3 </span><a name="cupsSideChannelDoRequest">cupsSideChannelDoRequest</a></h3>
+first.
+
+</p>
+<h3 class="function"><span class="info"> CUPS 1.4/Mac OS X 10.6 </span><a name="cupsBackendReport">cupsBackendReport</a></h3>
+<p class="description">Write a device line from a backend.</p>
+<p class="code">
+void cupsBackendReport (<br>
+ const char *device_scheme,<br>
+ const char *device_uri,<br>
+ const char *device_make_and_model,<br>
+ const char *device_info,<br>
+ const char *device_id,<br>
+ const char *device_location<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>device_scheme</dt>
+<dd class="description">device-scheme string</dd>
+<dt>device_uri</dt>
+<dd class="description">device-uri string</dd>
+<dt>device_make_and_model</dt>
+<dd class="description">device-make-and-model string or <code>NULL</code></dd>
+<dt>device_info</dt>
+<dd class="description">device-info string or <code>NULL</code></dd>
+<dt>device_id</dt>
+<dd class="description">device-id string or <code>NULL</code></dd>
+<dt>device_location</dt>
+<dd class="description">device-location string or <code>NULL</code></dd>
+</dl>
+<h4 class="discussion">Discussion</h4>
+<p class="discussion">This function writes a single device line to stdout for a backend.
+It handles quoting of special characters in the device-make-and-model,
+device-info, device-id, and device-location strings.
+
+</p>
+<h3 class="function"><span class="info"> CUPS 1.3/Mac OS X 10.5 </span><a name="cupsSideChannelDoRequest">cupsSideChannelDoRequest</a></h3>
<p class="description">Send a side-channel command to a backend and wait for a response.</p>
<p class="code">
<a href="#cups_sc_status_t">cups_sc_status_t</a> cupsSideChannelDoRequest (<br>
update the value to contain the number of data bytes in the buffer.
</p>
-<h3 class="function"><span class="info"> CUPS 1.3 </span><a name="cupsSideChannelRead">cupsSideChannelRead</a></h3>
+<h3 class="function"><span class="info"> CUPS 1.3
/Mac OS X 10.5 </span><a name="cupsSideChannelRead">cupsSideChannelRead</a></h3>
<p class="description">Read a side-channel message.</p>
<p class="code">
int cupsSideChannelRead (<br>
update the value to contain the number of data bytes in the buffer.
</p>
-<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSideChannelSNMPGet">cupsSideChannelSNMPGet</a></h3>
+<h3 class="function"><span class="info"> CUPS 1.4
/Mac OS X 10.6 </span><a name="cupsSideChannelSNMPGet">cupsSideChannelSNMPGet</a></h3>
<p class="description">Query a SNMP OID's value.</p>
<p class="code">
<a href="#cups_sc_status_t">cups_sc_status_t</a> cupsSideChannelSNMPGet (<br>
the printer does not respond to the SNMP query.
</p>
-<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSideChannelSNMPWalk">cupsSideChannelSNMPWalk</a></h3>
+<h3 class="function"><span class="info"> CUPS 1.4
/Mac OS X 10.6 </span><a name="cupsSideChannelSNMPWalk">cupsSideChannelSNMPWalk</a></h3>
<p class="description">Query multiple SNMP OID values.</p>
<p class="code">
<a href="#cups_sc_status_t">cups_sc_status_t</a> cupsSideChannelSNMPWalk (<br>
the printer does not respond to the first SNMP query.
</p>
-<h3 class="function"><span class="info"> CUPS 1.3 </span><a name="cupsSideChannelWrite">cupsSideChannelWrite</a></h3>
+<h3 class="function"><span class="info"> CUPS 1.3
/Mac OS X 10.5 </span><a name="cupsSideChannelWrite">cupsSideChannelWrite</a></h3>
<p class="description">Write a side-channel message.</p>
<p class="code">
int cupsSideChannelWrite (<br>
<dd class="description">Job failed, stop queue</dd>
</dl>
<h3 class="enumeration"><a name="cups_sc_bidi_e">cups_sc_bidi_e</a></h3>
-<p class="description">Bidirectional capabilities</p>
+<p class="description">Bidirectional capability values</p>
<h4 class="constants">Constants</h4>
<dl>
<dt>CUPS_SC_BIDI_NOT_SUPPORTED </dt>
<dd class="description">Return the IEEE-1284 device ID</dd>
<dt>CUPS_SC_CMD_GET_STATE </dt>
<dd class="description">Return the device state</dd>
-<dt>CUPS_SC_CMD_SNMP_GET <span class="info"> CUPS 1.4 </span></dt>
+<dt>CUPS_SC_CMD_SNMP_GET <span class="info"> CUPS 1.4/Mac OS X 10.6 </span></dt>
<dd class="description">Query an SNMP OID </dd>
-<dt>CUPS_SC_CMD_SNMP_GET_NEXT <span class="info"> CUPS 1.4 </span></dt>
+<dt>CUPS_SC_CMD_SNMP_GET_NEXT <span class="info"> CUPS 1.4/Mac OS X 10.6 </span></dt>
<dd class="description">Query the next SNMP OID </dd>
<dt>CUPS_SC_CMD_SOFT_RESET </dt>
<dd class="description">Do a soft reset</dd>
<dt>CUPS_SC_STATE_MEDIA_LOW </dt>
<dd class="description">Paper low condition</dd>
<dt>CUPS_SC_STATE_OFFLINE </dt>
-<dd class="description">Device is off-line</dd>
+<dd class="description">Device is offline</dd>
<dt>CUPS_SC_STATE_ONLINE </dt>
-<dd class="description">Device is on-line</dd>
+<dd class="description">Device is online</dd>
</dl>
<h3 class="enumeration"><a name="cups_sc_status_e">cups_sc_status_e</a></h3>
<p class="description">Response status codes</p>
projects / thirdparty / cups.git / blobdiff