div.contents ul.contents {
font-size: 80%;
}
+div.contents ul.subcontents li {
+ margin-left: 1em;
+ text-indent: -1em;
+}
--></style>
</head>
<body>
<div class='body'>
<!--
- "$Id: api-cups.header 7279 2008-01-31 01:50:44Z mike $"
+ "$Id: api-filter.header 7285 2008-02-01 23:57:39Z mike $"
Filter and backend programming header for the Common UNIX Printing System
(CUPS).
<div class='summary'><table summary='General Information'>
<thead>
<tr>
- <th>Header</th>
+ <th>Headers</th>
<th>cups/backend.h<br>
- cups/sidechannel.h</th>
+ cups/sidechannel.h<br>
+ cups/snmp.h</th>
</tr>
</thead>
<tbody>
<ul class="contents">
</li>
<li><a href="#OVERVIEW">Overview</a><ul class="subcontents">
+<li><a href="#SECURITY">Security Considerations</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="#ENVIRONMENT">Environment Variables</a></li>
<li><a href="#MESSAGES">Communicating with the Scheduler</a></li>
<li><a href="#COMMUNICATING">Communicating with the Backend</a></li>
+<li><a href="#SNMP">Doing SNMP Queries with Network Printers</a></li>
</ul></li>
<li><a href="#FUNCTIONS">Functions</a><ul class="code">
<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="#cupsSNMPClose" title="Close a SNMP socket.">cupsSNMPClose</a></li>
+<li><a href="#cupsSNMPCopyOID" title="Copy an OID.">cupsSNMPCopyOID</a></li>
+<li><a href="#cupsSNMPDefaultCommunity" title="Get the default SNMP community name.">cupsSNMPDefaultCommunity</a></li>
+<li><a href="#cupsSNMPIsOID" title="Test whether a SNMP response contains the specified OID.">cupsSNMPIsOID</a></li>
+<li><a href="#cupsSNMPIsOIDPrefixed" title="Test whether a SNMP response uses the specified
+OID prefix.">cupsSNMPIsOIDPrefixed</a></li>
+<li><a href="#cupsSNMPOpen" title="Open a SNMP socket.">cupsSNMPOpen</a></li>
+<li><a href="#cupsSNMPRead" title="Read and parse a SNMP response.">cupsSNMPRead</a></li>
+<li><a href="#cupsSNMPSetDebug" title="Enable/disable debug logging to stderr.">cupsSNMPSetDebug</a></li>
+<li><a href="#cupsSNMPWalk" title="Enumerate a group of OIDs.">cupsSNMPWalk</a></li>
+<li><a href="#cupsSNMPWrite" title="Send an SNMP query packet.">cupsSNMPWrite</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="#cupsSideChannelWrite" title="Write a side-channel message.">cupsSideChannelWrite</a></li>
</ul>
<li><a href="#TYPES">Data Types</a><ul class="code">
+ <li><a href="#cups_asn1_t" title="ASN1 request/object types">cups_asn1_t</a></li>
<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>
<li><a href="#cups_sc_command_t" title="Request command codes">cups_sc_command_t</a></li>
<li><a href="#cups_sc_state_t" title="Printer state bits">cups_sc_state_t</a></li>
<li><a href="#cups_sc_status_t" title="Response status codes">cups_sc_status_t</a></li>
+ <li><a href="#cups_snmp_cb_t" title="Prototypes...">cups_snmp_cb_t</a></li>
+ <li><a href="#cups_snmp_t" title="SNMP data packet">cups_snmp_t</a></li>
+</ul></li>
+<li><a href="#STRUCTURES">Structures</a><ul class="code">
+ <li><a href="#cups_snmp_hexstring_s" title="Hex-STRING value">cups_snmp_hexstring_s</a></li>
+ <li><a href="#cups_snmp_s" title="SNMP data packet">cups_snmp_s</a></li>
+</ul></li>
+<li><a href="#UNIONS">Unions</a><ul class="code">
+ <li><a href="#cups_snmp_value_u" title="Object value">cups_snmp_value_u</a></li>
</ul></li>
<li><a href="#ENUMERATIONS">Constants</a><ul class="code">
+ <li><a href="#cups_asn1_e" title="ASN1 request/object types">cups_asn1_e</a></li>
<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_command_e" title="Request command codes">cups_sc_command_e</a></li>
</ul></li>
</ul>
<!--
- "$Id: api-filter.shtml 6649 2007-07-11 21:46:42Z mike $"
+ "$Id: api-filter.shtml 7288 2008-02-06 01:39:05Z mike $"
Filter and backend programming introduction for the Common UNIX Printing
System (CUPS).
output. The backend is the last filter in the chain and writes to the
device.</p>
+<h3><a name="SECURITY">Security Considerations</a></h3>
+
+<p>It is always important to use security programming practices. Filters and
+most backends are run as a non-priviledged user, so the major security
+consideration is resource utilization - filters should not depend on unlimited
+amounts of CPU, memory, or disk space, and should protect against conditions
+that could lead to excess usage of any resource like infinite loops and
+unbounded recursion. In addition, filters must <em>never</em> allow the user to
+specify an arbitrary file path to a separator page, template, or other file
+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
+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
+where to store a file.</p>
+
+<blockquote><b>Note:</b>
+
+<p><em>Never</em> write files to a user's home directory. Aside from the
+security implications, CUPS is a network print service and as such the network
+user may not be the same as the local user and/or there may not be a local home
+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
+Mac OS X, for example, no backend may write to a user's home directory.</p>
+</blockquote>
+
+<h3><a name="TEMPFILES">Temporary Files</a></h3>
+
+<p>Temporary files should be created in the directory specified by the
+"TMPDIR" environment variable. The
+<a href="#cupsTempFile2"><code>cupsTempFile2</code></a> function can be
+used to safely create temporary files in this directory.</p>
+
+<h3><a name="COPIES">Copy Generation</a></h3>
+
+<p>The <code>argv[4]</code> argument specifies the number of copies to produce
+of the input file. In general, you should only generate copies if the
+<em>filename</em> argument is supplied. The only exception to this are
+filters that produce device-independent PostScript output, since the PostScript
+filter <var>pstops</var> is responsible for generating copies of PostScript
+files.</p>
+
<h3><a name="EXITCODES">Exit Codes</a></h3>
<p>Filters must exit with status 0 when they successfully generate print data
<a href="#cupsSideChannelWrite">cupsSideChannelWrite</a>(command, status, data, datalen, 1.0);
}
</pre>
+
+<h3><a name="SNMP">Doing SNMP Queries with Network Printers</a></h3>
+
+<p>The Simple Network Management Protocol (SNMP) allows you to get the current
+status, page counter, and supply levels from most network printers. Every
+piece of information is associated with an Object Identifier (OID), and
+every printer has a <em>community</em> name associated with it. OIDs can be
+queried directly or by "walking" over a range of OIDs with a common prefix.</p>
+
+<p>The CUPS SNMP functions provide a simple API for querying network printers.
+Queries are made using a datagram socket that is created using
+<a href="#cupsSNMPOpen"><code>cupsSNMPOpen</code></a> and destroyed using
+<a href="#cupsSNMPClose"><code>cupsSNMPClose</code></a>:</p>
+
+<pre class="example">
+#include <cups/snmp.h>
+
+int snmp = <a href="#cupsSNMPOpen">cupsSNMPOpen</a>(AF_INET);
+
+/* do some queries */
+
+<a href="#cupsSNMPClose">cupsSNMPClose</a>(snmp);
+</pre>
+
+<p>OIDs are simple C arrays of integers, terminated by a value of -1. For
+example, the page counter OID .1.3.6.1.2.1.43.10.2.1.4.1.1 would be:</p>
+
+<pre class="example">
+int page_counter_oid[] = { 1, 3, 6, 1, 2, 1, 43, 10, 2, 1, 4, 1, 1, -1 };
+</pre>
+
+<p>You send a query using
+<a href="#cupsSNMPWrite"><code>cupsSNMPWrite</code></a> and read the value back
+using <a href="#cupsSNMPRead"><code>cupsSNMPRead</code></a>. The value is read
+into a structure called <a href="#cups_snmp_t"><code>cups_snmp_t</code></a>:</p>
+
+<pre class="example">
+#include <cups/snmp.h>
+
+int page_counter_oid[] = { 1, 3, 6, 1, 2, 1, 43, 10, 2, 1, 4, 1, 1, -1 };
+http_addrlist_t *host = httpAddrGetList("myprinter", AF_UNSPEC, "161");
+int snmp = <a href="#cupsSNMPOpen">cupsSNMPOpen</a>(host->addr.addr.sa_family);
+<a href="#cups_snmp_t">cups_snmp_t</a> packet;
+
+<a href="#cupsSNMPWrite">cupsSNMPWrite</a>(snmp, &(host->addr), CUPS_SNMP_VERSION_1,
+ <a href="#cupsSNMPDefaultCommunity">cupsSNMPDefaultCommunity</a>(), CUPS_ASN1_GET_REQUEST, 1,
+ page_counter_oid);
+if (<a href="#cupsSNMPRead">cupsSNMPRead</a>(snmp, &packet, 5000))
+{
+ /* Do something with the value */
+ printf("Page counter is: %d\n", packet.object_value.integer);
+}
+</pre>
+
+<p>The <a href="#cupsSNMPWalk"><code>cupsSNMPWalk</code></a> function allows you
+to query a whole group of OIDs, calling a function of your choice for each OID
+that is found:</p>
+
+<pre class="example">
+#include <cups/snmp.h>
+
+void
+my_callback(<a href="#cups_snmp_t">cups_snmp_t</a> *packet, void *data)
+{
+ /* Do something with the value */
+}
+
+int printer_mib_oid[] = { 1, 3, 6, 1, 2, 1, 43, -1 };
+http_addrlist_t *host = httpAddrGetList("myprinter", AF_UNSPEC, "161");
+int snmp = <a href="#cupsSNMPOpen">cupsSNMPOpen</a>(host->addr.addr.sa_family);
+void *my_data;
+
+<a href="#cupsSNMPWalk">cupsSNMPWalk</a>(snmp, &(host->addr), CUPS_SNMP_VERSION_1,
+ <a href="#cupsSNMPDefaultCommunity">cupsSNMPDefaultCommunity</a>(), printer_mib_oid, 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>
<p class="description">Read data from the backchannel.</p>
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>
+<p class="description">Get the device URI for a backend.</p>
+<p class="code">
+const char *cupsBackendDeviceURI (<br>
+ char **argv<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>argv</dt>
+<dd class="description">Command-line arguments</dd>
+</dl>
+<h4 class="returnvalue">Return Value</h4>
+<p class="description">Device URI or <code>NULL</code></p>
+<h4 class="discussion">Discussion</h4>
+<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 1.4 </span><a name="cupsSNMPClose">cupsSNMPClose</a></h3>
+<p class="description">Close a SNMP socket.</p>
+<p class="code">
+void cupsSNMPClose (<br>
+ int fd<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>fd</dt>
+<dd class="description">SNMP socket file descriptor</dd>
+</dl>
+<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSNMPCopyOID">cupsSNMPCopyOID</a></h3>
+<p class="description">Copy an OID.</p>
+<p class="code">
+int *cupsSNMPCopyOID (<br>
+ int *dst,<br>
+ const int *src,<br>
+ int dstsize<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>dst</dt>
+<dd class="description">Destination OID</dd>
+<dt>src</dt>
+<dd class="description">Source OID</dd>
+<dt>dstsize</dt>
+<dd class="description">Number of integers in dst</dd>
+</dl>
+<h4 class="returnvalue">Return Value</h4>
+<p class="description">New OID</p>
+<h4 class="discussion">Discussion</h4>
+<p class="discussion">The array pointed to by "src" is terminated by the value -1.
+
+</p>
+<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSNMPDefaultCommunity">cupsSNMPDefaultCommunity</a></h3>
+<p class="description">Get the default SNMP community name.</p>
+<p class="code">
+const char *cupsSNMPDefaultCommunity (void);</p>
+<h4 class="returnvalue">Return Value</h4>
+<p class="description">Default community name</p>
+<h4 class="discussion">Discussion</h4>
+<p class="discussion">The default community name is the first community name found in the
+snmp.conf file. If no community name is defined there, "public" is used.
+
+</p>
+<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSNMPIsOID">cupsSNMPIsOID</a></h3>
+<p class="description">Test whether a SNMP response contains the specified OID.</p>
+<p class="code">
+int cupsSNMPIsOID (<br>
+ <a href="#cups_snmp_t">cups_snmp_t</a> *packet,<br>
+ const int *oid<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>packet</dt>
+<dd class="description">Response packet</dd>
+<dt>oid</dt>
+<dd class="description">OID</dd>
+</dl>
+<h4 class="returnvalue">Return Value</h4>
+<p class="description">1 if equal, 0 if not equal</p>
+<h4 class="discussion">Discussion</h4>
+<p class="discussion">The array pointed to by "oid" is terminated by the value -1.
+
+</p>
+<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSNMPIsOIDPrefixed">cupsSNMPIsOIDPrefixed</a></h3>
+<p class="description">Test whether a SNMP response uses the specified
+OID prefix.</p>
+<p class="code">
+int cupsSNMPIsOIDPrefixed (<br>
+ <a href="#cups_snmp_t">cups_snmp_t</a> *packet,<br>
+ const int *prefix<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>packet</dt>
+<dd class="description">Response packet</dd>
+<dt>prefix</dt>
+<dd class="description">OID prefix</dd>
+</dl>
+<h4 class="returnvalue">Return Value</h4>
+<p class="description">1 if prefixed, 0 if not prefixed</p>
+<h4 class="discussion">Discussion</h4>
+<p class="discussion">The array pointed to by "prefix" is terminated by the value -1.
+
+</p>
+<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSNMPOpen">cupsSNMPOpen</a></h3>
+<p class="description">Open a SNMP socket.</p>
+<p class="code">
+int cupsSNMPOpen (<br>
+ int family<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>family</dt>
+<dd class="description">Address family - <code>AF_INET</code> or <code>AF_INET6</code></dd>
+</dl>
+<h4 class="returnvalue">Return Value</h4>
+<p class="description">SNMP socket file descriptor</p>
+<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSNMPRead">cupsSNMPRead</a></h3>
+<p class="description">Read and parse a SNMP response.</p>
+<p class="code">
+<a href="#cups_snmp_t">cups_snmp_t</a> *cupsSNMPRead (<br>
+ int fd,<br>
+ <a href="#cups_snmp_t">cups_snmp_t</a> *packet,<br>
+ int msec<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>fd</dt>
+<dd class="description">SNMP socket file descriptor</dd>
+<dt>packet</dt>
+<dd class="description">SNMP packet buffer</dd>
+<dt>msec</dt>
+<dd class="description">Timeout in milliseconds</dd>
+</dl>
+<h4 class="returnvalue">Return Value</h4>
+<p class="description">SNMP packet or <code>NULL</code> if none</p>
+<h4 class="discussion">Discussion</h4>
+<p class="discussion">If "timeout" is negative, <code>cupsSNMPRead</code> will wait for a response
+indefinitely.
+
+</p>
+<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSNMPSetDebug">cupsSNMPSetDebug</a></h3>
+<p class="description">Enable/disable debug logging to stderr.</p>
+<p class="code">
+void cupsSNMPSetDebug (<br>
+ int level<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>level</dt>
+<dd class="description">1 to enable debug output, 0 otherwise</dd>
+</dl>
+<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSNMPWalk">cupsSNMPWalk</a></h3>
+<p class="description">Enumerate a group of OIDs.</p>
+<p class="code">
+int cupsSNMPWalk (<br>
+ int fd,<br>
+ http_addr_t *address,<br>
+ int version,<br>
+ const char *community,<br>
+ const int *prefix,<br>
+ int msec,<br>
+ <a href="#cups_snmp_cb_t">cups_snmp_cb_t</a> cb,<br>
+ void *data<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>fd</dt>
+<dd class="description">SNMP socket</dd>
+<dt>address</dt>
+<dd class="description">Address to query</dd>
+<dt>version</dt>
+<dd class="description">SNMP version</dd>
+<dt>community</dt>
+<dd class="description">Community name</dd>
+<dt>prefix</dt>
+<dd class="description">OID prefix</dd>
+<dt>msec</dt>
+<dd class="description">Timeout for each response in milliseconds</dd>
+<dt>cb</dt>
+<dd class="description">Function to call for each response</dd>
+<dt>data</dt>
+<dd class="description">User data pointer that is passed to the callback function</dd>
+</dl>
+<h4 class="returnvalue">Return Value</h4>
+<p class="description">Number of OIDs found or -1 on error</p>
+<h4 class="discussion">Discussion</h4>
+<p class="discussion">This function queries all of the OIDs with the specified OID prefix,
+calling the "cb" function for every response that is received.<br>
+<br>
+The array pointed to by "prefix" is terminated by the value -1.
+
+</p>
+<h3 class="function"><span class="info"> CUPS 1.4 </span><a name="cupsSNMPWrite">cupsSNMPWrite</a></h3>
+<p class="description">Send an SNMP query packet.</p>
+<p class="code">
+int cupsSNMPWrite (<br>
+ int fd,<br>
+ http_addr_t *address,<br>
+ int version,<br>
+ const char *community,<br>
+ <a href="#cups_asn1_t">cups_asn1_t</a> request_type,<br>
+ const unsigned request_id,<br>
+ const int *oid<br>
+);</p>
+<h4 class="parameters">Parameters</h4>
+<dl>
+<dt>fd</dt>
+<dd class="description">SNMP socket</dd>
+<dt>address</dt>
+<dd class="description">Address to send to</dd>
+<dt>version</dt>
+<dd class="description">SNMP version</dd>
+<dt>community</dt>
+<dd class="description">Community name</dd>
+<dt>request_type</dt>
+<dd class="description">Request type</dd>
+<dt>request_id</dt>
+<dd class="description">Request ID</dd>
+<dt>oid</dt>
+<dd class="description">OID</dd>
+</dl>
+<h4 class="returnvalue">Return Value</h4>
+<p class="description">1 on success, 0 on error</p>
+<h4 class="discussion">Discussion</h4>
+<p class="discussion">The array pointed to by "oid" is terminated by the value -1.
+
</p>
<h3 class="function"><span class="info"> CUPS 1.3 </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>
<h2 class="title"><a name="TYPES">Data Types</a></h2>
+<h3 class="typedef"><a name="cups_asn1_t">cups_asn1_t</a></h3>
+<p class="description">ASN1 request/object types</p>
+<p class="code">
+typedef enum <a href="#cups_asn1_e">cups_asn1_e</a> cups_asn1_t;
+</p>
<h3 class="typedef"><a name="cups_backend_t">cups_backend_t</a></h3>
<p class="description">Backend exit codes</p>
<p class="code">
<p class="code">
typedef enum <a href="#cups_sc_status_e">cups_sc_status_e</a> cups_sc_status_t;
</p>
+<h3 class="typedef"><a name="cups_snmp_cb_t">cups_snmp_cb_t</a></h3>
+<p class="description">Prototypes...</p>
+<p class="code">
+typedef void (*cups_snmp_cb_t)(<a href="#cups_snmp_t">cups_snmp_t</a> *packet, void *data);
+</p>
+<h3 class="typedef"><a name="cups_snmp_t">cups_snmp_t</a></h3>
+<p class="description">SNMP data packet</p>
+<p class="code">
+typedef struct <a href="#cups_snmp_s">cups_snmp_s</a> cups_snmp_t;
+</p>
+<h2 class="title"><a name="STRUCTURES">Structures</a></h2>
+<h3 class="struct"><a name="cups_snmp_hexstring_s">cups_snmp_hexstring_s</a></h3>
+<p class="description">Hex-STRING value</p>
+<p class="code">struct cups_snmp_hexstring_s {<br>
+ unsigned char bytes[CUPS_SNMP_MAX_STRING];<br>
+ int num_bytes;<br>
+};</p>
+<h4 class="members">Members</h4>
+<dl>
+<dt>bytes[CUPS_SNMP_MAX_STRING] </dt>
+<dd class="description">Bytes in string</dd>
+<dt>num_bytes </dt>
+<dd class="description">Number of bytes</dd>
+</dl>
+<h3 class="struct"><a name="cups_snmp_s">cups_snmp_s</a></h3>
+<p class="description">SNMP data packet</p>
+<p class="code">struct cups_snmp_s {<br>
+ http_addr_t address;<br>
+ char community[CUPS_SNMP_MAX_STRING];<br>
+ const char *error;<br>
+ int error_index;<br>
+ int error_status;<br>
+ int object_name[CUPS_SNMP_MAX_OID];<br>
+ <a href="#cups_asn1_t">cups_asn1_t</a> object_type;<br>
+ union <a href="#cups_snmp_value_u">cups_snmp_value_u</a> object_value;<br>
+ int request_id;<br>
+ <a href="#cups_asn1_t">cups_asn1_t</a> request_type;<br>
+ int version;<br>
+};</p>
+<h4 class="members">Members</h4>
+<dl>
+<dt>address </dt>
+<dd class="description">Source address</dd>
+<dt>community[CUPS_SNMP_MAX_STRING] </dt>
+<dd class="description">Community name</dd>
+<dt>error </dt>
+<dd class="description">Encode/decode error</dd>
+<dt>error_index </dt>
+<dd class="description">error-index value</dd>
+<dt>error_status </dt>
+<dd class="description">error-status value</dd>
+<dt>object_name[CUPS_SNMP_MAX_OID] </dt>
+<dd class="description">object-name value</dd>
+<dt>object_type </dt>
+<dd class="description">object-value type</dd>
+<dt>object_value </dt>
+<dd class="description">object-value value</dd>
+<dt>request_id </dt>
+<dd class="description">request-id value</dd>
+<dt>request_type </dt>
+<dd class="description">Request type</dd>
+<dt>version </dt>
+<dd class="description">Version number</dd>
+</dl>
+<h2 class="title"><a name="UNIONS">Unions</a></h2>
+<h3 class="union"><a name="cups_snmp_value_u">cups_snmp_value_u</a></h3>
+<p class="description">Object value</p>
+<p class="code">union cups_snmp_value_u {<br>
+ int boolean;<br>
+ unsigned counter;<br>
+ unsigned gauge;<br>
+ struct <a href="#cups_snmp_hexstring_s">cups_snmp_hexstring_s</a> hex_string;<br>
+ int integer;<br>
+ int oid[CUPS_SNMP_MAX_OID];<br>
+ char string[CUPS_SNMP_MAX_STRING];<br>
+ unsigned timeticks;<br>
+};</p>
+<h4 class="members">Members</h4>
+<dl>
+<dt>boolean </dt>
+<dd class="description">Boolean value</dd>
+<dt>counter </dt>
+<dd class="description">Counter value</dd>
+<dt>gauge </dt>
+<dd class="description">Gauge value</dd>
+<dt>hex_string </dt>
+<dd class="description">Hex string value</dd>
+<dt>integer </dt>
+<dd class="description">Integer value</dd>
+<dt>oid[CUPS_SNMP_MAX_OID] </dt>
+<dd class="description">OID value</dd>
+<dt>string[CUPS_SNMP_MAX_STRING] </dt>
+<dd class="description">String value</dd>
+<dt>timeticks </dt>
+<dd class="description">Timeticks value</dd>
+</dl>
<h2 class="title"><a name="ENUMERATIONS">Constants</a></h2>
+<h3 class="enumeration"><a name="cups_asn1_e">cups_asn1_e</a></h3>
+<p class="description">ASN1 request/object types</p>
+<h4 class="constants">Constants</h4>
+<dl>
+<dt>CUPS_ASN1_BIT_STRING </dt>
+<dd class="description">BIT STRING</dd>
+<dt>CUPS_ASN1_BOOLEAN </dt>
+<dd class="description">BOOLEAN</dd>
+<dt>CUPS_ASN1_COUNTER </dt>
+<dd class="description">32-bit unsigned aka Counter32</dd>
+<dt>CUPS_ASN1_END_OF_CONTENTS </dt>
+<dd class="description">End-of-contents</dd>
+<dt>CUPS_ASN1_GAUGE </dt>
+<dd class="description">32-bit unsigned aka Gauge32</dd>
+<dt>CUPS_ASN1_GET_NEXT_REQUEST </dt>
+<dd class="description">GetNextRequest-PDU</dd>
+<dt>CUPS_ASN1_GET_REQUEST </dt>
+<dd class="description">GetRequest-PDU</dd>
+<dt>CUPS_ASN1_GET_RESPONSE </dt>
+<dd class="description">GetResponse-PDU</dd>
+<dt>CUPS_ASN1_HEX_STRING </dt>
+<dd class="description">Binary string aka Hex-STRING</dd>
+<dt>CUPS_ASN1_INTEGER </dt>
+<dd class="description">INTEGER or ENUMERATION</dd>
+<dt>CUPS_ASN1_NULL_VALUE </dt>
+<dd class="description">NULL VALUE</dd>
+<dt>CUPS_ASN1_OCTET_STRING </dt>
+<dd class="description">OCTET STRING</dd>
+<dt>CUPS_ASN1_OID </dt>
+<dd class="description">OBJECT IDENTIFIER</dd>
+<dt>CUPS_ASN1_SEQUENCE </dt>
+<dd class="description">SEQUENCE</dd>
+<dt>CUPS_ASN1_TIMETICKS </dt>
+<dd class="description">32-bit unsigned aka Timeticks32</dd>
+</dl>
<h3 class="enumeration"><a name="cups_backend_e">cups_backend_e</a></h3>
<p class="description">Backend exit codes</p>
<h4 class="constants">Constants</h4>
projects / thirdparty / cups.git / blobdiff