doc/help/api-filter.html

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 255 <!--
 256   "$Id: api-filter.header 7616 2008-05-28 00:34:13Z mike $"
 257
 258   Filter and backend programming header for the Common UNIX Printing System
 259   (CUPS).
 260
 261   Copyright 2008 by Apple Inc.
 262
 263   These coded instructions, statements, and computer programs are the
 264   property of Apple Inc. and are protected by Federal copyright
 265   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
 266   which should have been included with this file.  If this file is
 267   file is missing or damaged, see the license at "http://www.cups.org/".
 268 -->
 269
 270 <h1 class="title">Filter and Backend Programming</h1>
 271
 272 <div class='summary'><table summary='General Information'>
 273 <thead>
 274 <tr>
 275         <th>Headers</th>
 276         <th>cups/backend.h<br>
 277         cups/sidechannel.h</th>
 278 </tr>
 279 </thead>
 280 <tbody>
 281 <tr>
 282         <th>Library</th>
 283         <td>-lcups</td>
 284 </tr>
 285 <tr>
 286         <th>See Also</th>
 287         <td>Programming: <a href='api-overview.html' target='_top'>Introduction to CUPS Programming</a><br>
 288         Programming: <a href='api-cups.html' target='_top'>CUPS API</a><br>
 289         Programming: <a href='api-ppd.html' target='_top'>PPD API</a><br>
 290         Programming: <a href='api-raster.html' target='_top'>Raster API</a><br>
 291         Specifications: <a href='spec-design' target='_top'>CUPS Design Description</a></td>
 292 </tr>
 293 </tbody>
 294 </table></div>
 295 <h2 class="title">Contents</h2>
 296 <ul class="contents">
 297 </li>
 298 <li><a href="#OVERVIEW">Overview</a><ul class="subcontents">
 299 <li><a href="#SECURITY">Security Considerations</a></li>
 300 <li><a href="#TEMPFILES">Temporary Files</a></li>
 301 <li><a href="#COPIES">Copy Generation</a></li>
 302 <li><a href="#EXITCODES">Exit Codes</a></li>
 303 <li><a href="#ENVIRONMENT">Environment Variables</a></li>
 304 <li><a href="#MESSAGES">Communicating with the Scheduler</a></li>
 305 <li><a href="#COMMUNICATING_BACKEND">Communicating with the Backend</a></li>
 306 <li><a href="#COMMUNICATING_FILTER">Communicating with Filters</a></li>
 307 <li><a href="#SNMP">Doing SNMP Queries with Network Printers</a></li>
 308 </ul></li>
 309 <li><a href="#FUNCTIONS">Functions</a><ul class="code">
 310 <li><a href="#cupsBackChannelRead" title="Read data from the backchannel.">cupsBackChannelRead</a></li>
 311 <li><a href="#cupsBackChannelWrite" title="Write data to the backchannel.">cupsBackChannelWrite</a></li>
 312 <li><a href="#cupsBackendDeviceURI" title="Get the device URI for a backend.">cupsBackendDeviceURI</a></li>
 313 <li><a href="#cupsSideChannelDoRequest" title="Send a side-channel command to a backend and wait for a response.">cupsSideChannelDoRequest</a></li>
 314 <li><a href="#cupsSideChannelRead" title="Read a side-channel message.">cupsSideChannelRead</a></li>
 315 <li><a href="#cupsSideChannelSNMPGet" title="Query a SNMP OID's value.">cupsSideChannelSNMPGet</a></li>
 316 <li><a href="#cupsSideChannelSNMPWalk" title="Query multiple SNMP OID values.">cupsSideChannelSNMPWalk</a></li>
 317 <li><a href="#cupsSideChannelWrite" title="Write a side-channel message.">cupsSideChannelWrite</a></li>
 318 </ul>
 319 <li><a href="#TYPES">Data Types</a><ul class="code">
 320         <li><a href="#cups_backend_t" title="Backend exit codes">cups_backend_t</a></li>
 321         <li><a href="#cups_sc_bidi_t" title="Bidirectional capabilities">cups_sc_bidi_t</a></li>
 322         <li><a href="#cups_sc_command_t" title="Request command codes">cups_sc_command_t</a></li>
 323         <li><a href="#cups_sc_state_t" title="Printer state bits">cups_sc_state_t</a></li>
 324         <li><a href="#cups_sc_status_t" title="Response status codes">cups_sc_status_t</a></li>
 325         <li><a href="#cups_sc_walk_func_t" title="SNMP walk callback">cups_sc_walk_func_t</a></li>
 326 </ul></li>
 327 <li><a href="#ENUMERATIONS">Constants</a><ul class="code">
 328         <li><a href="#cups_backend_e" title="Backend exit codes">cups_backend_e</a></li>
 329         <li><a href="#cups_sc_bidi_e" title="Bidirectional capability values">cups_sc_bidi_e</a></li>
 330         <li><a href="#cups_sc_command_e" title="Request command codes">cups_sc_command_e</a></li>
 331         <li><a href="#cups_sc_state_e" title="Printer state bits">cups_sc_state_e</a></li>
 332         <li><a href="#cups_sc_status_e" title="Response status codes">cups_sc_status_e</a></li>
 333 </ul></li>
 334 </ul>
 335 <!--
 336   "$Id: api-filter.shtml 7677 2008-06-19 23:22:19Z mike $"
 337
 338   Filter and backend programming introduction for the Common UNIX Printing
 339   System (CUPS).
 340
 341   Copyright 2007-2008 by Apple Inc.
 342   Copyright 1997-2006 by Easy Software Products, all rights reserved.
 343
 344   These coded instructions, statements, and computer programs are the
 345   property of Apple Inc. and are protected by Federal copyright
 346   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
 347   which should have been included with this file.  If this file is
 348   file is missing or damaged, see the license at "http://www.cups.org/".
 349 -->
 350
 351 <h2 class='title'><a name="OVERVIEW">Overview</a></h2>
 352
 353 <p>Filters (which include printer drivers and port monitors) and backends
 354 are used to convert job files to a printable format and send that data to the
 355 printer itself. All of these programs use a common interface for processing
 356 print jobs and communicating status information to the scheduler. Each is run
 357 with a standard set of command-line arguments:<p>
 358
 359 <dl class="code">
 360
 361         <dt>argv[1]</dt>
 362         <dd>The job ID</dd>
 363
 364         <dt>argv[2]</dt>
 365         <dd>The user printing the job</dd>
 366
 367         <dt>argv[3]</dt>
 368         <dd>The job name/title</dd>
 369
 370         <dt>argv[4]</dt>
 371         <dd>The number of copies to print</dd>
 372
 373         <dt>argv[5]</dt>
 374         <dd>The options that were provided when the job was submitted</dd>
 375
 376         <dt>argv[6]</dt>
 377         <dd>The file to print (first program only)</dd>
 378 </dl>
 379
 380 <p>The scheduler runs one or more of these programs to print any given job. The
 381 first filter reads from the print file and writes to the standard output, while
 382 the remaining filters read from the standard input and write to the standard
 383 output. The backend is the last filter in the chain and writes to the
 384 device.</p>
 385
 386 <h3><a name="SECURITY">Security Considerations</a></h3>
 387
 388 <p>It is always important to use security programming practices. Filters and
 389 most backends are run as a non-priviledged user, so the major security
 390 consideration is resource utilization - filters should not depend on unlimited
 391 amounts of CPU, memory, or disk space, and should protect against conditions
 392 that could lead to excess usage of any resource like infinite loops and
 393 unbounded recursion. In addition, filters must <em>never</em> allow the user to
 394 specify an arbitrary file path to a separator page, template, or other file
 395 used by the filter since that can lead to an unauthorized disclosure of
 396 information. <em>Always</em> treat input as suspect and validate it!</p>
 397
 398 <p>If you are developing a backend that runs as root, make sure to check for
 399 potential buffer overflows, integer under/overflow conditions, and file
 400 accesses since these can lead to privilege escalations. When writing files,
 401 always validate the file path and <em>never</em> allow a user to determine
 402 where to store a file.</p>
 403
 404 <blockquote><b>Note:</b>
 405
 406 <p><em>Never</em> write files to a user's home directory. Aside from the
 407 security implications, CUPS is a network print service and as such the network
 408 user may not be the same as the local user and/or there may not be a local home
 409 directory to write to.</p>
 410
 411 <p>In addition, some operating systems provide additional security mechanisms
 412 that further limit file system access, even for backends running as root.  On
 413 Mac OS X, for example, no backend may write to a user's home directory.</p>
 414 </blockquote>
 415
 416 <h3><a name="TEMPFILES">Temporary Files</a></h3>
 417
 418 <p>Temporary files should be created in the directory specified by the
 419 "TMPDIR" environment variable. The
 420 <a href="#cupsTempFile2"><code>cupsTempFile2</code></a> function can be
 421 used to safely create temporary files in this directory.</p>
 422
 423 <h3><a name="COPIES">Copy Generation</a></h3>
 424
 425 <p>The <code>argv[4]</code> argument specifies the number of copies to produce
 426 of the input file. In general, you should only generate copies if the
 427 <em>filename</em> argument is supplied. The only exception to this are
 428 filters that produce device-independent PostScript output, since the PostScript
 429 filter <var>pstops</var> is responsible for generating copies of PostScript
 430 files.</p>
 431
 432 <h3><a name="EXITCODES">Exit Codes</a></h3>
 433
 434 <p>Filters must exit with status 0 when they successfully generate print data
 435 or 1 when they encounter an error. Backends can return any of the
 436 <a href="#cups_backend_t"><code>cups_backend_t</code></a> constants.</p>
 437
 438 <h3><a name="ENVIRONMENT">Environment Variables</a></h3>
 439
 440 <p>The following environment variables are defined by the printing system
 441 when running print filters and backends:</p>
 442
 443 <dl class="code">
 444
 445         <dt>APPLE_LANGUAGES</dt>
 446         <dd>The Apple language identifier associated with the job
 447         (Mac OS X only).</dd>
 448
 449         <dt>CHARSET</dt>
 450         <dd>The job character set, typically "utf-8".</dd>
 451
 452         <dt>CLASS</dt>
 453         <dd>When a job is submitted to a printer class, contains the name of
 454         the destination printer class. Otherwise this environment
 455         variable will not be set.</dd>
 456
 457         <dt>CONTENT_TYPE</dt>
 458         <dd>The MIME type associated with the file (e.g.
 459         application/postscript).</dd>
 460
 461         <dt>CUPS_CACHEDIR</dt>
 462         <dd>The directory where cache files can be stored. Cache files can be
 463         used to retain information between jobs or files in a job.</dd>
 464
 465         <dt>CUPS_DATADIR</dt>
 466         <dd>The directory where (read-only) CUPS data files can be found.</dd>
 467
 468         <dt>CUPS_SERVERROOT</dt>
 469         <dd>The root directory of the server.</dd>
 470
 471         <dt>DEVICE_URI</dt>
 472         <dd>The device-uri associated with the printer.</dd>
 473
 474         <dt>FINAL_CONTENT_TYPE</dt>
 475         <dd>The MIME type associated with the printer (e.g.
 476         application/vnd.cups-postscript).</dd>
 477
 478         <dt>LANG</dt>
 479         <dd>The language locale associated with the job.</dd>
 480
 481         <dt>PPD</dt>
 482         <dd>The full pathname of the PostScript Printer Description (PPD)
 483         file for this printer.</dd>
 484
 485         <dt>PRINTER</dt>
 486         <dd>The queue name of the class or printer.</dd>
 487
 488         <dt>RIP_CACHE</dt>
 489         <dd>The recommended amount of memory to use for Raster Image
 490         Processors (RIPs).</dd>
 491
 492         <dt>TMPDIR</dt>
 493         <dd>The directory where temporary files should be created.</dd>
 494
 495 </dl>
 496
 497 <h3><a name="MESSAGES">Communicating with the Scheduler</a></h3>
 498
 499 <p>Filters and backends communicate with the scheduler by writing messages
 500 to the standard error file. The scheduler reads messages from all filters in
 501 a job and processes the message based on its prefix. For example, the following
 502 code sets the current printer state message to "Printing page 5":</p>
 503
 504 <pre class="example">
 505 int page = 5;
 506
 507 fprintf(stderr, "INFO: Printing page %d\n", page);
 508 </pre>
 509
 510 <p>Each message is a single line of text starting with one of the following
 511 prefix strings:</p>
 512
 513 <dl class="code">
 514
 515         <dt>ALERT: message</dt>
 516         <dd>Sets the printer-state-message attribute and adds the specified
 517         message to the current error log file using the "alert" log level.</dd>
 518
 519         <dt>ATTR: attribute=value [attribute=value]</dt>
 520         <dd>Sets the named printer or job attribute(s). Typically this is used
 521         to set the <code>marker-colors</code>, <code>marker-levels</code>,
 522         <code>marker-message</code>, <code>marker-names</code>,
 523         <code>marker-types</code>, <code>printer-alert</code>, and
 524         <code>printer-alert-description</code> printer attributes. Standard
 525         <code>marker-types</code> values are listed in <a href='#TABLE1'>Table
 526         1</a>.</dd>
 527
 528         <dt>CRIT: message</dt>
 529         <dd>Sets the printer-state-message attribute and adds the specified
 530         message to the current error log file using the "critical" log
 531         level.</dd>
 532
 533         <dt>DEBUG: message</dt>
 534         <dd>Sets the printer-state-message attribute and adds the specified
 535         message to the current error log file using the "debug" log level.</dd>
 536
 537         <dt>DEBUG2: message</dt>
 538         <dd>Sets the printer-state-message attribute and adds the specified
 539         message to the current error log file using the "debug2" log level.</dd>
 540
 541         <dt>EMERG: message</dt>
 542         <dd>Sets the printer-state-message attribute and adds the specified
 543         message to the current error log file using the "emergency" log
 544         level.</dd>
 545
 546         <dt>ERROR: message</dt>
 547         <dd>Sets the printer-state-message attribute and adds the specified
 548         message to the current error log file using the "error" log level.
 549         Use "ERROR:" messages for non-persistent processing errors.</dd>
 550
 551         <dt>INFO: message</dt>
 552         <dd>Sets the printer-state-message attribute. If the current log level
 553         is set to "debug2", also adds the specified message to the current error
 554         log file using the "info" log level.</dd>
 555
 556         <dt>NOTICE: message</dt>
 557         <dd>Sets the printer-state-message attribute and adds the specified
 558         message to the current error log file using the "notice" log level.</dd>
 559
 560         <dt>PAGE: page-number #-copies</dt>
 561         <dt>PAGE: total #-pages</dt>
 562         <dd>Adds an entry to the current page log file. The first form adds
 563         #-copies to the job-media-sheets-completed attribute. The second
 564         form sets the job-media-sheets-completed attribute to #-pages.</dd>
 565
 566         <dt>PPD: keyword=value [keyword=value ...]</dt>
 567         <dd>Changes or adds keywords to the printer's PPD file. Typically
 568         this is used to update installable options or default media settings
 569         based on the printer configuration.</dd>
 570
 571         <dt>STATE: printer-state-reason [printer-state-reason ...]</dt>
 572         <dt>STATE: + printer-state-reason [printer-state-reason ...]</dt>
 573         <dt>STATE: - printer-state-reason [printer-state-reason ...]</dt>
 574         <dd>Sets, adds, or removes printer-state-reason keywords to the
 575         current queue. Typically this is used to indicate persistent media,
 576         ink, toner, and configuration conditions or errors on a printer.
 577         <a href='#TABLE2'>Table 2</a> lists the standard state keywords -
 578         use vendor-prefixed ("com.acme.foo") keywords for custom states.</dd>
 579
 580         <dt>WARNING: message</dt>
 581         <dd>Sets the printer-state-message attribute and adds the specified
 582         message to the current error log file using the "warning" log
 583         level.</dd>
 584
 585 </dl>
 586
 587 <p>Messages without one of these prefixes are treated as if they began with
 588 the "DEBUG:" prefix string.</p>
 589
 590
 591 <div class='table'><table width='80%' summary='Table 1: Standard marker-types Values'>
 592 <caption>Table 1: <a name='TABLE1'>Standard marker-types Values</a></caption>
 593 <thead>
 594 <tr>
 595         <th>marker-type</th>
 596         <th>Description</th>
 597 </tr>
 598 </thead>
 599 <tbody>
 600 <tr>
 601         <td>developer</td>
 602         <td>Developer unit</td>
 603 </tr>
 604 <tr>
 605         <td>fuser</td>
 606         <td>Fuser unit</td>
 607 </tr>
 608 <tr>
 609         <td>fuserCleaningPad</td>
 610         <td>Fuser cleaning pad</td>
 611 </tr>
 612 <tr>
 613         <td>fuserOil</td>
 614         <td>Fuser oil</td>
 615 </tr>
 616 <tr>
 617         <td>ink</td>
 618         <td>Ink supply</td>
 619 </tr>
 620 <tr>
 621         <td>opc</td>
 622         <td>Photo conductor</td>
 623 </tr>
 624 <tr>
 625         <td>solidWax</td>
 626         <td>Wax supply</td>
 627 </tr>
 628 <tr>
 629         <td>staples</td>
 630         <td>Staple supply</td>
 631 </tr>
 632 <tr>
 633         <td>toner</td>
 634         <td>Toner supply</td>
 635 </tr>
 636 <tr>
 637         <td>transferUnit</td>
 638         <td>Transfer unit</td>
 639 </tr>
 640 <tr>
 641         <td>wasteInk</td>
 642         <td>Waste ink tank</td>
 643 </tr>
 644 <tr>
 645         <td>wasteToner</td>
 646         <td>Waste toner tank</td>
 647 </tr>
 648 <tr>
 649         <td>wasteWax</td>
 650         <td>Waste wax tank</td>
 651 </tr>
 652 </tbody>
 653 </table></div>
 654
 655 <br>
 656
 657 <div class='table'><table width='80%' summary='Table 2: Standard State Keywords'>
 658 <caption>Table 2: <a name='TABLE2'>Standard State Keywords</a></caption>
 659 <thead>
 660 <tr>
 661         <th>Keyword</th>
 662         <th>Description</th>
 663 </tr>
 664 </thead>
 665 <tbody>
 666 <tr>
 667         <td>connecting-to-device</td>
 668         <td>Connecting to printer but not printing yet</td>
 669 </tr>
 670 <tr>
 671         <td>cover-open</td>
 672         <td>A cover is open on the printer</td>
 673 </tr>
 674 <tr>
 675         <td>input-tray-missing</td>
 676         <td>An input tray is missing from the printer</td>
 677 </tr>
 678 <tr>
 679         <td>marker-supply-empty</td>
 680         <td>Out of ink</td>
 681 </tr>
 682 <tr>
 683         <td>marker-supply-low</td>
 684         <td>Low on ink</td>
 685 </tr>
 686 <tr>
 687         <td>marker-waste-almost-full</td>
 688         <td>Waste tank almost full</td>
 689 </tr>
 690 <tr>
 691         <td>marker-waste-full</td>
 692         <td>Waste tank full</td>
 693 </tr>
 694 <tr>
 695         <td>media-empty</td>
 696         <td>Out of media</td>
 697 </tr>
 698 <tr>
 699         <td>media-jam</td>
 700         <td>Media is jammed in the printer</td>
 701 </tr>
 702 <tr>
 703         <td>media-low</td>
 704         <td>Low on media</td>
 705 </tr>
 706 <tr>
 707         <td>paused</td>
 708         <td>Stop the printer</td>
 709 </tr>
 710 <tr>
 711         <td>timed-out</td>
 712         <td>Unable to connect to printer</td>
 713 </tr>
 714 <tr>
 715         <td>toner-empty</td>
 716         <td>Out of toner</td>
 717 </tr>
 718 <tr>
 719         <td>toner-low</td>
 720         <td>Low on toner</td>
 721 </tr>
 722 </tbody>
 723 </table></div>
 724
 725 <h3><a name="COMMUNICATING_BACKEND">Communicating with the Backend</a></h3>
 726
 727 <p>Filters can communicate with the backend via the
 728 <a href="#cupsBackChannelRead"><code>cupsBackChannelRead</code></a> and
 729 <a href="#cupsSideChannelDoRequest"><code>cupsSideChannelDoRequest</code></a>
 730 functions. The
 731 <a href="#cupsBackChannelRead"><code>cupsBackChannelRead</code></a> function
 732 reads data that has been sent back from the device and is typically used to
 733 obtain status and configuration information. For example, the following code
 734 polls the backend for back-channel data:</p>
 735
 736 <pre class="example">
 737 #include &lt;cups/cups.h&gt;
 738
 739 char buffer[8192];
 740 ssize_t bytes;
 741
 742 /* Use a timeout of 0.0 seconds to poll for back-channel data */
 743 bytes = cupsBackChannelRead(buffer, sizeof(buffer), 0.0);
 744 </pre>
 745
 746 <p>Filters can also use <code>select()</code> or <code>poll()</code> on the
 747 back-channel file descriptor (3 or <code>CUPS_BC_FD</code>) to read data only
 748 when it is available.</p>
 749
 750 <p>The
 751 <a href="#cupsSideChannelDoRequest"><code>cupsSideChannelDoRequest</code></a>
 752 function allows you to get out-of-band status information and do synchronization
 753 with the device. For example, the following code gets the current IEEE-1284
 754 device ID string from the backend:</p>
 755
 756 <pre class="example">
 757 #include &lt;cups/sidechannel.h&gt;
 758
 759 char data[2049];
 760 int datalen;
 761 <a href="#cups_sc_status_t">cups_sc_status_t</a> status;
 762
 763 /* Tell cupsSideChannelDoRequest() how big our buffer is, less 1 byte for
 764    nul-termination... */
 765 datalen = sizeof(data) - 1;
 766
 767 /* Get the IEEE-1284 device ID, waiting for up to 1 second */
 768 status = <a href="#cupsSideChannelDoRequest">cupsSideChannelDoRequest</a>(CUPS_SC_CMD_GET_DEVICE_ID, data, &amp;datalen, 1.0);
 769
 770 /* Use the returned value if OK was returned and the length is non-zero */
 771 if (status == CUPS_SC_STATUS_OK && datalen > 0)
 772   data[datalen] = '\0';
 773 else
 774   data[0] = '\0';
 775 </pre>
 776
 777 <h3><a name="COMMUNICATING_FILTER">Communicating with Filters</a></h3>
 778
 779 <p>Backends communicate with filters using the reciprocal functions
 780 <a href="#cupsBackChannelWrite"><code>cupsBackChannelWrite</code></a>,
 781 <a href="#cupsSideChannelRead"><code>cupsSideChannelRead</code></a>, and
 782 <a href="#cupsSideChannelWrite"><code>cupsSideChannelWrite</code></a>. We
 783 recommend writing back-channel data using a timeout of 1.0 seconds:</p>
 784
 785 <pre class="example">
 786 #include &lt;cups/cups.h&gt;
 787
 788 char buffer[8192];
 789 ssize_t bytes;
 790
 791 /* Obtain data from printer/device */
 792 ...
 793
 794 /* Use a timeout of 1.0 seconds to give filters a chance to read */
 795 cupsBackChannelWrite(buffer, bytes, 1.0);
 796 </pre>
 797
 798 <p>The <a href="#cupsSideChannelRead"><code>cupsSideChannelRead</code></a>
 799 function reads a side-channel command from a filter, driver, or port monitor.
 800 Backends can either poll for commands using a <code>timeout</code> of 0.0, wait
 801 indefinitely for commands using a <code>timeout</code> of -1.0 (probably in a
 802 separate thread for that purpose), or use <code>select</code> or
 803 <code>poll</code> on the <code>CUPS_SC_FD</code> file descriptor (4) to handle
 804 input and output on several file descriptors at the same time.</p>
 805
 806 <p>Once a command is processed, the backend uses the
 807 <a href="#cupsSideChannelWrite"><code>cupsSideChannelWrite</code></a> function
 808 to send its response. For example, the following code shows how to poll for a
 809 side-channel command and respond to it:</p>
 810
 811 <pre class="example">
 812 #include &lt;cups/sidechannel.h&gt;
 813
 814 <a href="#cups_sc_command_t">cups_sc_command_t</a> command;
 815 <a href="#cups_sc_status_t">cups_sc_status_t</a> status;
 816 char data[2048];
 817 int datalen = sizeof(data);
 818
 819 /* Poll for a command... */
 820 if (!<a href="#cupsSideChannelRead">cupsSideChannelRead</a>(&amp;command, &amp;status, data, &amp;datalen, 0.0))
 821 {
 822   switch (command)
 823   {
 824     /* handle supported commands, fill data/datalen/status with values as needed */
 825
 826     default :
 827         status  = CUPS_SC_STATUS_NOT_IMPLEMENTED;
 828         datalen = 0;
 829         break;
 830   }
 831
 832   /* Send a response... */
 833   <a href="#cupsSideChannelWrite">cupsSideChannelWrite</a>(command, status, data, datalen, 1.0);
 834 }
 835 </pre>
 836
 837 <h3><a name="SNMP">Doing SNMP Queries with Network Printers</a></h3>
 838
 839 <p>The Simple Network Management Protocol (SNMP) allows you to get the current
 840 status, page counter, and supply levels from most network printers. Every
 841 piece of information is associated with an Object Identifier (OID), and
 842 every printer has a <em>community</em> name associated with it. OIDs can be
 843 queried directly or by "walking" over a range of OIDs with a common prefix.</p>
 844
 845 <p>The two CUPS SNMP functions provide a simple API for querying network
 846 printers through the side-channel interface. Each accepts a string containing
 847 an OID like ".1.3.6.1.2.1.43.10.2.1.4.1.1" (the standard page counter OID)
 848 along with a timeout for the query.</p>
 849
 850 <p>The <a href="#cupsSideChannelSNMPGet"><code>cupsSideChannelSNMPGet</code></a>
 851 function queries a single OID and returns the value as a string in a buffer
 852 you supply:</p>
 853
 854 <pre class="example">
 855 #include &lt;cups/sidechannel.h&gt;
 856
 857 char data[512];
 858 int datalen = sizeof(data);
 859
 860 if (<a href="#cupsSideChannelSNMPGet">cupsSideChannelSNMPGet</a>(".1.3.6.1.2.1.43.10.2.1.4.1.1", data, &amp;datalen, 5.0)
 861         == CUPS_SC_STATUS_OK)
 862 {
 863   /* Do something with the value */
 864   printf("Page counter is: %s\n", data);
 865 }
 866 </pre>
 867
 868 <p>The
 869 <a href="#cupsSideChannelSNMPWalk"><code>cupsSideChannelSNMPWalk</code></a>
 870 function allows you to query a whole group of OIDs, calling a function of your
 871 choice for each OID that is found:</p>
 872
 873 <pre class="example">
 874 #include &lt;cups/sidechannel.h&gt;
 875
 876 void
 877 my_callback(const char *oid, const char *data, int datalen, void *context)
 878 {
 879   /* Do something with the value */
 880   printf("%s=%s\n", oid, data);
 881 }
 882
 883 ...
 884
 885 void *my_data;
 886
 887 <a href="#cupsSideChannelSNMPWalk">cupsSNMPSideChannelWalk</a>(".1.3.6.1.2.1.43", 5.0, my_callback, my_data);
 888 </pre>
 889 <h2 class="title"><a name="FUNCTIONS">Functions</a></h2>
 890 <h3 class="function"><span class="info">&nbsp;CUPS 1.2&nbsp;</span><a name="cupsBackChannelRead">cupsBackChannelRead</a></h3>
 891 <p class="description">Read data from the backchannel.</p>
 892 <p class="code">
 893 ssize_t cupsBackChannelRead (<br>
 894 &nbsp;&nbsp;&nbsp;&nbsp;char *buffer,<br>
 895 &nbsp;&nbsp;&nbsp;&nbsp;size_t bytes,<br>
 896 &nbsp;&nbsp;&nbsp;&nbsp;double timeout<br>
 897 );</p>
 898 <h4 class="parameters">Parameters</h4>
 899 <dl>
 900 <dt>buffer</dt>
 901 <dd class="description">Buffer to read into</dd>
 902 <dt>bytes</dt>
 903 <dd class="description">Bytes to read</dd>
 904 <dt>timeout</dt>
 905 <dd class="description">Timeout in seconds, typically 0.0 to poll</dd>
 906 </dl>
 907 <h4 class="returnvalue">Return Value</h4>
 908 <p class="description">Bytes read or -1 on error</p>
 909 <h4 class="discussion">Discussion</h4>
 910 <p class="discussion">Reads up to &quot;bytes&quot; bytes from the backchannel/backend. The &quot;timeout&quot;
 911 parameter controls how many seconds to wait for the data - use 0.0 to
 912 return immediately if there is no data, -1.0 to wait for data indefinitely.
 913
 914 </p>
 915 <h3 class="function"><span class="info">&nbsp;CUPS 1.2&nbsp;</span><a name="cupsBackChannelWrite">cupsBackChannelWrite</a></h3>
 916 <p class="description">Write data to the backchannel.</p>
 917 <p class="code">
 918 ssize_t cupsBackChannelWrite (<br>
 919 &nbsp;&nbsp;&nbsp;&nbsp;const char *buffer,<br>
 920 &nbsp;&nbsp;&nbsp;&nbsp;size_t bytes,<br>
 921 &nbsp;&nbsp;&nbsp;&nbsp;double timeout<br>
 922 );</p>
 923 <h4 class="parameters">Parameters</h4>
 924 <dl>
 925 <dt>buffer</dt>
 926 <dd class="description">Buffer to write</dd>
 927 <dt>bytes</dt>
 928 <dd class="description">Bytes to write</dd>
 929 <dt>timeout</dt>
 930 <dd class="description">Timeout in seconds, typically 1.0</dd>
 931 </dl>
 932 <h4 class="returnvalue">Return Value</h4>
 933 <p class="description">Bytes written or -1 on error</p>
 934 <h4 class="discussion">Discussion</h4>
 935 <p class="discussion">Writes &quot;bytes&quot; bytes to the backchannel/filter. The &quot;timeout&quot; parameter
 936 controls how many seconds to wait for the data to be written - use
 937 0.0 to return immediately if the data cannot be written, -1.0 to wait
 938 indefinitely.
 939
 940 </p>
 941 <h3 class="function"><a name="cupsBackendDeviceURI">cupsBackendDeviceURI</a></h3>
 942 <p class="description">Get the device URI for a backend.</p>
 943 <p class="code">
 944 const char *cupsBackendDeviceURI (<br>
 945 &nbsp;&nbsp;&nbsp;&nbsp;char **argv<br>
 946 );</p>
 947 <h4 class="parameters">Parameters</h4>
 948 <dl>
 949 <dt>argv</dt>
 950 <dd class="description">Command-line arguments</dd>
 951 </dl>
 952 <h4 class="returnvalue">Return Value</h4>
 953 <p class="description">Device URI or <code>NULL</code></p>
 954 <h4 class="discussion">Discussion</h4>
 955 <p class="discussion">The &quot;argv&quot; argument is the argv argument passed to main(). This
 956 function returns the device URI passed in the DEVICE_URI environment
 957 variable or the device URI passed in argv[0], whichever is found
 958 first.</p>
 959 <h3 class="function"><span class="info">&nbsp;CUPS 1.3&nbsp;</span><a name="cupsSideChannelDoRequest">cupsSideChannelDoRequest</a></h3>
 960 <p class="description">Send a side-channel command to a backend and wait for a response.</p>
 961 <p class="code">
 962 <a href="#cups_sc_status_t">cups_sc_status_t</a> cupsSideChannelDoRequest (<br>
 963 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#cups_sc_command_t">cups_sc_command_t</a> command,<br>
 964 &nbsp;&nbsp;&nbsp;&nbsp;char *data,<br>
 965 &nbsp;&nbsp;&nbsp;&nbsp;int *datalen,<br>
 966 &nbsp;&nbsp;&nbsp;&nbsp;double timeout<br>
 967 );</p>
 968 <h4 class="parameters">Parameters</h4>
 969 <dl>
 970 <dt>command</dt>
 971 <dd class="description">Command to send</dd>
 972 <dt>data</dt>
 973 <dd class="description">Response data buffer pointer</dd>
 974 <dt>datalen</dt>
 975 <dd class="description">Size of data buffer on entry, number of bytes in buffer on return</dd>
 976 <dt>timeout</dt>
 977 <dd class="description">Timeout in seconds</dd>
 978 </dl>
 979 <h4 class="returnvalue">Return Value</h4>
 980 <p class="description">Status of command</p>
 981 <h4 class="discussion">Discussion</h4>
 982 <p class="discussion">This function is normally only called by filters, drivers, or port
 983 monitors in order to communicate with the backend used by the current
 984 printer.  Programs must be prepared to handle timeout or &quot;not
 985 implemented&quot; status codes, which indicate that the backend or device
 986 do not support the specified side-channel command.<br>
 987 <br>
 988 The &quot;datalen&quot; parameter must be initialized to the size of the buffer
 989 pointed to by the &quot;data&quot; parameter.  cupsSideChannelDoRequest() will
 990 update the value to contain the number of data bytes in the buffer.
 991
 992 </p>
 993 <h3 class="function"><span class="info">&nbsp;CUPS 1.3&nbsp;</span><a name="cupsSideChannelRead">cupsSideChannelRead</a></h3>
 994 <p class="description">Read a side-channel message.</p>
 995 <p class="code">
 996 int cupsSideChannelRead (<br>
 997 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#cups_sc_command_t">cups_sc_command_t</a> *command,<br>
 998 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#cups_sc_status_t">cups_sc_status_t</a> *status,<br>
 999 &nbsp;&nbsp;&nbsp;&nbsp;char *data,<br>
1000 &nbsp;&nbsp;&nbsp;&nbsp;int *datalen,<br>
1001 &nbsp;&nbsp;&nbsp;&nbsp;double timeout<br>
1002 );</p>
1003 <h4 class="parameters">Parameters</h4>
1004 <dl>
1005 <dt>command</dt>
1006 <dd class="description">Command code</dd>
1007 <dt>status</dt>
1008 <dd class="description">Status code</dd>
1009 <dt>data</dt>
1010 <dd class="description">Data buffer pointer</dd>
1011 <dt>datalen</dt>
1012 <dd class="description">Size of data buffer on entry, number of bytes in buffer on return</dd>
1013 <dt>timeout</dt>
1014 <dd class="description">Timeout in seconds</dd>
1015 </dl>
1016 <h4 class="returnvalue">Return Value</h4>
1017 <p class="description">0 on success, -1 on error</p>
1018 <h4 class="discussion">Discussion</h4>
1019 <p class="discussion">This function is normally only called by backend programs to read
1020 commands from a filter, driver, or port monitor program.  The
1021 caller must be prepared to handle incomplete or invalid messages
1022 and return the corresponding status codes.<br>
1023 <br>
1024 The &quot;datalen&quot; parameter must be initialized to the size of the buffer
1025 pointed to by the &quot;data&quot; parameter.  cupsSideChannelDoRequest() will
1026 update the value to contain the number of data bytes in the buffer.
1027
1028 </p>
1029 <h3 class="function"><span class="info">&nbsp;CUPS 1.4&nbsp;</span><a name="cupsSideChannelSNMPGet">cupsSideChannelSNMPGet</a></h3>
1030 <p class="description">Query a SNMP OID's value.</p>
1031 <p class="code">
1032 <a href="#cups_sc_status_t">cups_sc_status_t</a> cupsSideChannelSNMPGet (<br>
1033 &nbsp;&nbsp;&nbsp;&nbsp;const char *oid,<br>
1034 &nbsp;&nbsp;&nbsp;&nbsp;char *data,<br>
1035 &nbsp;&nbsp;&nbsp;&nbsp;int *datalen,<br>
1036 &nbsp;&nbsp;&nbsp;&nbsp;double timeout<br>
1037 );</p>
1038 <h4 class="parameters">Parameters</h4>
1039 <dl>
1040 <dt>oid</dt>
1041 <dd class="description">OID to query</dd>
1042 <dt>data</dt>
1043 <dd class="description">Buffer for OID value</dd>
1044 <dt>datalen</dt>
1045 <dd class="description">Size of OID buffer on entry, size of value on return</dd>
1046 <dt>timeout</dt>
1047 <dd class="description">Timeout in seconds</dd>
1048 </dl>
1049 <h4 class="returnvalue">Return Value</h4>
1050 <p class="description">Query status</p>
1051 <h4 class="discussion">Discussion</h4>
1052 <p class="discussion">This function asks the backend to do a SNMP OID query on behalf of the
1053 filter, port monitor, or backend using the default community name.<br>
1054 <br>
1055 &quot;oid&quot; contains a numeric OID consisting of integers separated by periods,
1056 for example &quot;.1.3.6.1.2.1.43&quot;.  Symbolic names from SNMP MIBs are not
1057 supported and must be converted to their numeric forms.<br>
1058 <br>
1059 On input, &quot;data&quot; and &quot;datalen&quot; provide the location and size of the
1060 buffer to hold the OID value as a string. HEX-String (binary) values are
1061 converted to hexadecimal strings representing the binary data, while
1062 NULL-Value and unknown OID types are returned as the empty string.
1063 The returned &quot;datalen&quot; does not include the trailing nul.
1064
1065 <code>CUPS_SC_STATUS_NOT_IMPLEMENTED</code> is returned by backends that do not
1066 support SNMP queries.  <code>CUPS_SC_STATUS_NO_RESPONSE</code> is returned when
1067 the printer does not respond to the SNMP query.
1068
1069 </p>
1070 <h3 class="function"><span class="info">&nbsp;CUPS 1.4&nbsp;</span><a name="cupsSideChannelSNMPWalk">cupsSideChannelSNMPWalk</a></h3>
1071 <p class="description">Query multiple SNMP OID values.</p>
1072 <p class="code">
1073 <a href="#cups_sc_status_t">cups_sc_status_t</a> cupsSideChannelSNMPWalk (<br>
1074 &nbsp;&nbsp;&nbsp;&nbsp;const char *oid,<br>
1075 &nbsp;&nbsp;&nbsp;&nbsp;double timeout,<br>
1076 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#cups_sc_walk_func_t">cups_sc_walk_func_t</a> cb,<br>
1077 &nbsp;&nbsp;&nbsp;&nbsp;void *context<br>
1078 );</p>
1079 <h4 class="parameters">Parameters</h4>
1080 <dl>
1081 <dt>oid</dt>
1082 <dd class="description">First numeric OID to query</dd>
1083 <dt>timeout</dt>
1084 <dd class="description">Timeout for each query in seconds</dd>
1085 <dt>cb</dt>
1086 <dd class="description">Function to call with each value</dd>
1087 <dt>context</dt>
1088 <dd class="description">Application-defined pointer to send to callback</dd>
1089 </dl>
1090 <h4 class="returnvalue">Return Value</h4>
1091 <p class="description">Status of first query of <code>CUPS_SC_STATUS_OK</code> on success</p>
1092 <h4 class="discussion">Discussion</h4>
1093 <p class="discussion">This function asks the backend to do multiple SNMP OID queries on behalf
1094 of the filter, port monitor, or backend using the default community name.
1095 All OIDs under the &quot;parent&quot; OID are queried and the results are sent to
1096 the callback function you provide.<br>
1097 <br>
1098 &quot;oid&quot; contains a numeric OID consisting of integers separated by periods,
1099 for example &quot;.1.3.6.1.2.1.43&quot;.  Symbolic names from SNMP MIBs are not
1100 supported and must be converted to their numeric forms.<br>
1101 <br>
1102 &quot;timeout&quot; specifies the timeout for each OID query. The total amount of
1103 time will depend on the number of OID values found and the time required
1104 for each query.<br>
1105 <br>
1106 &quot;cb&quot; provides a function to call for every value that is found. &quot;context&quot;
1107 is an application-defined pointer that is sent to the callback function
1108 along with the OID and current data. The data passed to the callback is the
1109 same as returned by <a href="#cupsSideChannelSNMPGet"><code>cupsSideChannelSNMPGet</code></a>.
1110
1111 <code>CUPS_SC_STATUS_NOT_IMPLEMENTED</code> is returned by backends that do not
1112 support SNMP queries.  <code>CUPS_SC_STATUS_NO_RESPONSE</code> is returned when
1113 the printer does not respond to the first SNMP query.
1114
1115 </p>
1116 <h3 class="function"><span class="info">&nbsp;CUPS 1.3&nbsp;</span><a name="cupsSideChannelWrite">cupsSideChannelWrite</a></h3>
1117 <p class="description">Write a side-channel message.</p>
1118 <p class="code">
1119 int cupsSideChannelWrite (<br>
1120 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#cups_sc_command_t">cups_sc_command_t</a> command,<br>
1121 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#cups_sc_status_t">cups_sc_status_t</a> status,<br>
1122 &nbsp;&nbsp;&nbsp;&nbsp;const char *data,<br>
1123 &nbsp;&nbsp;&nbsp;&nbsp;int datalen,<br>
1124 &nbsp;&nbsp;&nbsp;&nbsp;double timeout<br>
1125 );</p>
1126 <h4 class="parameters">Parameters</h4>
1127 <dl>
1128 <dt>command</dt>
1129 <dd class="description">Command code</dd>
1130 <dt>status</dt>
1131 <dd class="description">Status code</dd>
1132 <dt>data</dt>
1133 <dd class="description">Data buffer pointer</dd>
1134 <dt>datalen</dt>
1135 <dd class="description">Number of bytes of data</dd>
1136 <dt>timeout</dt>
1137 <dd class="description">Timeout in seconds</dd>
1138 </dl>
1139 <h4 class="returnvalue">Return Value</h4>
1140 <p class="description">0 on success, -1 on error</p>
1141 <h4 class="discussion">Discussion</h4>
1142 <p class="discussion">This function is normally only called by backend programs to send
1143 responses to a filter, driver, or port monitor program.
1144
1145 </p>
1146 <h2 class="title"><a name="TYPES">Data Types</a></h2>
1147 <h3 class="typedef"><a name="cups_backend_t">cups_backend_t</a></h3>
1148 <p class="description">Backend exit codes</p>
1149 <p class="code">
1150 typedef enum <a href="#cups_backend_e">cups_backend_e</a> cups_backend_t;
1151 </p>
1152 <h3 class="typedef"><a name="cups_sc_bidi_t">cups_sc_bidi_t</a></h3>
1153 <p class="description">Bidirectional capabilities</p>
1154 <p class="code">
1155 typedef enum <a href="#cups_sc_bidi_e">cups_sc_bidi_e</a> cups_sc_bidi_t;
1156 </p>
1157 <h3 class="typedef"><a name="cups_sc_command_t">cups_sc_command_t</a></h3>
1158 <p class="description">Request command codes</p>
1159 <p class="code">
1160 typedef enum <a href="#cups_sc_command_e">cups_sc_command_e</a> cups_sc_command_t;
1161 </p>
1162 <h3 class="typedef"><a name="cups_sc_state_t">cups_sc_state_t</a></h3>
1163 <p class="description">Printer state bits</p>
1164 <p class="code">
1165 typedef enum <a href="#cups_sc_state_e">cups_sc_state_e</a> cups_sc_state_t;
1166 </p>
1167 <h3 class="typedef"><a name="cups_sc_status_t">cups_sc_status_t</a></h3>
1168 <p class="description">Response status codes</p>
1169 <p class="code">
1170 typedef enum <a href="#cups_sc_status_e">cups_sc_status_e</a> cups_sc_status_t;
1171 </p>
1172 <h3 class="typedef"><a name="cups_sc_walk_func_t">cups_sc_walk_func_t</a></h3>
1173 <p class="description">SNMP walk callback</p>
1174 <p class="code">
1175 typedef void (*cups_sc_walk_func_t)(const char *oid, const char *data, int datalen, void *context);
1176 </p>
1177 <h2 class="title"><a name="ENUMERATIONS">Constants</a></h2>
1178 <h3 class="enumeration"><a name="cups_backend_e">cups_backend_e</a></h3>
1179 <p class="description">Backend exit codes</p>
1180 <h4 class="constants">Constants</h4>
1181 <dl>
1182 <dt>CUPS_BACKEND_AUTH_REQUIRED </dt>
1183 <dd class="description">Job failed, authentication required</dd>
1184 <dt>CUPS_BACKEND_CANCEL </dt>
1185 <dd class="description">Job failed, cancel job</dd>
1186 <dt>CUPS_BACKEND_FAILED </dt>
1187 <dd class="description">Job failed, use error-policy</dd>
1188 <dt>CUPS_BACKEND_HOLD </dt>
1189 <dd class="description">Job failed, hold job</dd>
1190 <dt>CUPS_BACKEND_OK </dt>
1191 <dd class="description">Job completed successfully</dd>
1192 <dt>CUPS_BACKEND_STOP </dt>
1193 <dd class="description">Job failed, stop queue</dd>
1194 </dl>
1195 <h3 class="enumeration"><a name="cups_sc_bidi_e">cups_sc_bidi_e</a></h3>
1196 <p class="description">Bidirectional capability values</p>
1197 <h4 class="constants">Constants</h4>
1198 <dl>
1199 <dt>CUPS_SC_BIDI_NOT_SUPPORTED </dt>
1200 <dd class="description">Bidirectional I/O is not supported</dd>
1201 <dt>CUPS_SC_BIDI_SUPPORTED </dt>
1202 <dd class="description">Bidirectional I/O is supported</dd>
1203 </dl>
1204 <h3 class="enumeration"><a name="cups_sc_command_e">cups_sc_command_e</a></h3>
1205 <p class="description">Request command codes</p>
1206 <h4 class="constants">Constants</h4>
1207 <dl>
1208 <dt>CUPS_SC_CMD_DRAIN_OUTPUT </dt>
1209 <dd class="description">Drain all pending output</dd>
1210 <dt>CUPS_SC_CMD_GET_BIDI </dt>
1211 <dd class="description">Return bidirectional capabilities</dd>
1212 <dt>CUPS_SC_CMD_GET_DEVICE_ID </dt>
1213 <dd class="description">Return the IEEE-1284 device ID</dd>
1214 <dt>CUPS_SC_CMD_GET_STATE </dt>
1215 <dd class="description">Return the device state</dd>
1216 <dt>CUPS_SC_CMD_SNMP_GET <span class="info">&nbsp;CUPS 1.4&nbsp;</span></dt>
1217 <dd class="description">Query an SNMP OID </dd>
1218 <dt>CUPS_SC_CMD_SNMP_GET_NEXT <span class="info">&nbsp;CUPS 1.4&nbsp;</span></dt>
1219 <dd class="description">Query the next SNMP OID </dd>
1220 <dt>CUPS_SC_CMD_SOFT_RESET </dt>
1221 <dd class="description">Do a soft reset</dd>
1222 </dl>
1223 <h3 class="enumeration"><a name="cups_sc_state_e">cups_sc_state_e</a></h3>
1224 <p class="description">Printer state bits</p>
1225 <h4 class="constants">Constants</h4>
1226 <dl>
1227 <dt>CUPS_SC_STATE_BUSY </dt>
1228 <dd class="description">Device is busy</dd>
1229 <dt>CUPS_SC_STATE_ERROR </dt>
1230 <dd class="description">Other error condition</dd>
1231 <dt>CUPS_SC_STATE_MARKER_EMPTY </dt>
1232 <dd class="description">Toner/ink out condition</dd>
1233 <dt>CUPS_SC_STATE_MARKER_LOW </dt>
1234 <dd class="description">Toner/ink low condition</dd>
1235 <dt>CUPS_SC_STATE_MEDIA_EMPTY </dt>
1236 <dd class="description">Paper out condition</dd>
1237 <dt>CUPS_SC_STATE_MEDIA_LOW </dt>
1238 <dd class="description">Paper low condition</dd>
1239 <dt>CUPS_SC_STATE_OFFLINE </dt>
1240 <dd class="description">Device is offline</dd>
1241 <dt>CUPS_SC_STATE_ONLINE </dt>
1242 <dd class="description">Device is online</dd>
1243 </dl>
1244 <h3 class="enumeration"><a name="cups_sc_status_e">cups_sc_status_e</a></h3>
1245 <p class="description">Response status codes</p>
1246 <h4 class="constants">Constants</h4>
1247 <dl>
1248 <dt>CUPS_SC_STATUS_BAD_MESSAGE </dt>
1249 <dd class="description">The command/response message was invalid</dd>
1250 <dt>CUPS_SC_STATUS_IO_ERROR </dt>
1251 <dd class="description">An I/O error occurred</dd>
1252 <dt>CUPS_SC_STATUS_NONE </dt>
1253 <dd class="description">No status</dd>
1254 <dt>CUPS_SC_STATUS_NOT_IMPLEMENTED </dt>
1255 <dd class="description">Command not implemented</dd>
1256 <dt>CUPS_SC_STATUS_NO_RESPONSE </dt>
1257 <dd class="description">The device did not respond</dd>
1258 <dt>CUPS_SC_STATUS_OK </dt>
1259 <dd class="description">Operation succeeded</dd>
1260 <dt>CUPS_SC_STATUS_TIMEOUT </dt>
1261 <dd class="description">The backend did not respond</dd>
1262 <dt>CUPS_SC_STATUS_TOO_BIG </dt>
1263 <dd class="description">Response too big</dd>
1264 </dl>
1265 </div>
1266 </body>
1267 </html>