doc/help/api-admin.html

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 354 <div class='body'>
 355 <!--
 356   Administrative API header for CUPS.
 357
 358   Copyright 2016 by Apple Inc.
 359
 360   These coded instructions, statements, and computer programs are the
 361   property of Apple Inc. and are protected by Federal copyright
 362   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
 363   which should have been included with this file.  If this file is
 364   file is missing or damaged, see the license at "http://www.cups.org/".
 365 -->
 366
 367 <h1 class='title'>Administrative APIs</h1>
 368
 369 <div class='summary'><table summary='General Information'>
 370 <thead>
 371 <tr>
 372         <th>Header</th>
 373         <th>cups/adminutil.h</th>
 374 </tr>
 375 </thead>
 376 <tbody>
 377 <tr>
 378         <th>Library</th>
 379         <td>-lcups</td>
 380 </tr>
 381 <tr>
 382         <th>See Also</th>
 383         <td>Programming: <a href='api-overview.html' target='_top'>Introduction to CUPS Programming</a><br>
 384         Programming: <a href='api-cups.html' target='_top'>CUPS API</a><br>
 385         Programming: <a href='api-httpipp.html' target='_top'>HTTP and IPP APIs</a></td>
 386 </tr>
 387 </tbody>
 388 </table></div>
 389 <h2 class="title">Contents</h2>
 390 <ul class="contents">
 391 <li><a href="#OVERVIEW">Overview</a><ul class="subcontents">
 392         <li><a href="#SETTINGS">Scheduler Settings</a></li>
 393         <li><a href="#DEVICES">Devices</a></li>
 394 </ul></li>
 395 <li><a href="#FUNCTIONS">Functions</a><ul class="code">
 396         <li><a href="#cupsAdminCreateWindowsPPD" title="Create the Windows PPD file for a printer.">cupsAdminCreateWindowsPPD</a></li>
 397         <li><a href="#cupsAdminExportSamba" title="Export a printer to Samba.">cupsAdminExportSamba</a></li>
 398         <li><a href="#cupsAdminGetServerSettings" title="Get settings from the server.">cupsAdminGetServerSettings</a></li>
 399         <li><a href="#cupsAdminSetServerSettings" title="Set settings on the server.">cupsAdminSetServerSettings</a></li>
 400         <li><a href="#cupsGetDevices" title="Get available printer devices.">cupsGetDevices</a></li>
 401 </ul></li>
 402 <li><a href="#TYPES">Data Types</a><ul class="code">
 403         <li><a href="#cups_device_cb_t" title="Device callback
 404 ">cups_device_cb_t</a></li>
 405 </ul></li>
 406 </ul>
 407 <!--
 408   Administrative API documentation for CUPS.
 409
 410   Copyright 2016 by Apple Inc.
 411
 412   These coded instructions, statements, and computer programs are the
 413   property of Apple Inc. and are protected by Federal copyright
 414   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
 415   which should have been included with this file.  If this file is
 416   file is missing or damaged, see the license at "http://www.cups.org/".
 417 -->
 418
 419 <h2 class="title"><a name="OVERVIEW">Overview</a></h2>
 420
 421 <p>The administrative APIs provide convenience functions to perform certain administrative functions with the CUPS scheduler.</p>
 422
 423 <blockquote><b>Note:<b>
 424   <p>Administrative functions normally require administrative privileges to execute and must not be used in ordinary user applications!</p>
 425 </blockquote>
 426
 427 <h3><a name="SETTINGS">Scheduler Settings</a></h3>
 428
 429 <p>The <a href="#cupsAdminGetServerSettings"><code>cupsAdminGetServerSettings</code></a> and <a href="#cupsAdminSetServerSettings"><code>cupsAdminSetServerSettings</code></a> functions allow you to get and set simple directives and their values, respectively, in the <var>cupsd.conf</var> file for the CUPS scheduler. Settings are stored in CUPS option arrays which provide a simple list of string name/value pairs. While any simple <var>cupsd.conf</var> directive name can be specified, the following convenience names are also defined to control common complex directives:</p>
 430
 431 <ul>
 432   <li><code>CUPS_SERVER_DEBUG_LOGGING</code></li>: For <code>cupsAdminGetServerSettings</code>, a value of "1" means that the <code>LogLevel</code> directive is set to <code>debug</code> or <code>debug2</code> while a value of "0" means it is set to any other value. For <code>cupsAdminSetServerSettings</code> a value of "1" sets the <code>LogLeveL</code> to <code>debug</code> while a value of "0" sets it to <code>warn</code>.</li>
 433   <li><code>CUPS_SERVER_REMOTE_ADMIN</code></li>: A value of "1" specifies that administrative requests are accepted from remote addresses while "0" specifies that requests are only accepted from local addresses (loopback interface and domain sockets).</li>
 434   <li><code>CUPS_SERVER_REMOTE_ANY</code></li>: A value of "1" specifies that requests are accepts from any address while "0" specifies that requests are only accepted from the local subnet (when sharing is enabled) or local addresses (loopback interface and domain sockets).</li>
 435   <li><code>CUPS_SERVER_SHARE_PRINTERS</code></li>: A value of "1" specifies that printer sharing is enabled for selected printers and remote requests are accepted while a value of "0" specifies that printer sharing is disables and remote requests are not accepted.</li>
 436   <li><code>CUPS_SERVER_USER_CANCEL_ANY</code></li>: A value of "1" specifies that the default security policy allows any user to cancel any print job, regardless of the owner. A value of "0" specifies that only administrative users can cancel other user's jobs.</li>
 437 </ul>
 438
 439 <blockquote><b>Note:</b>
 440   <p>Changing settings will restart the CUPS scheduler.</p>
 441   <p>When printer sharing or the web interface are enabled, the scheduler's launch-on-demand functionality is effectively disabled. This can affect power usage, system performance, and the security profile of a system.</p>
 442 </blockquote>
 443
 444 <p>The recommended way to make changes to the <var>cupsd.conf</var> is to first call <a href="#cupsAdminGetServerSettings"><code>cupsAdminGetServerSettings</code></a>, make any changes to the returned option array, and then call <a href="#cupsAdminSetServerSettings"><code>cupsAdminSetServerSettings</code></a> to save those settings. For example, to enable the web interface:</p>
 445
 446 <pre class="example">
 447 #include &lt;cups/cups.h&gt;
 448 #include &lt;cups/adminutil.h&gt;
 449
 450 void
 451 enable_web_interface(void)
 452 {
 453   int num_settings = 0;           /* Number of settings */
 454   cups_option_t *settings = NULL; /* Settings */
 455
 456
 457   if (!<a href="#cupsAdminGetServerSettings">cupsAdminGetServerSettings</a>(CUPS_HTTP_DEFAULT, &amp;num_settings, &amp;settings))
 458   {
 459     fprintf(stderr, "ERROR: Unable to get server settings: %s\n", cupsLastErrorString());
 460     return;
 461   }
 462
 463   num_settings = <a href="api-cups.html#cupsAddOption">cupsAddOption</a>("WebInterface", "Yes", num_settings, &amp;settings);
 464
 465   if (!<a href="#cupsAdminSetServerSettings">cupsAdminSetServerSettings</a>(CUPS_HTTP_DEFAULT, num_settings, settings))
 466   {
 467     fprintf(stderr, "ERROR: Unable to set server settings: %s\n", cupsLastErrorString());
 468   }
 469
 470   <a href="api-cups.html#cupsFreeOptions">cupsFreeOptions</a>(num_settings, settings);
 471 }
 472 </pre>
 473
 474 <h3><a name="DEVICES">Devices</a></h3>
 475
 476 <p>Printers can be discovered through the CUPS scheduler using the <a href="#cupsGetDevices"><code>cupsGetDevices</code></a> API. Typically this API is used to locate printers to add the the system. Each device that is found will cause a supplied callback function to be executed. For example, to list the available printer devices that can be found within 30 seconds:</p>
 477
 478 <pre class="example">
 479 #include &lt;cups/cups.h&gt;
 480 #include &lt;cups/adminutil.h&gt;
 481
 482
 483 void
 484 get_devices_cb(
 485     const char *device_class,           /* I - Class */
 486     const char *device_id,              /* I - 1284 device ID */
 487     const char *device_info,            /* I - Description */
 488     const char *device_make_and_model,  /* I - Make and model */
 489     const char *device_uri,             /* I - Device URI */
 490     const char *device_location,        /* I - Location */
 491     void       *user_data)              /* I - User data */
 492 {
 493   puts(device_uri);
 494 }
 495
 496
 497 void
 498 show_devices(void)
 499 {
 500   <a href="#cupsGetDevices">cupsGetDevices</a>(CUPS_HTTP_DEFAULT, 30, NULL, NULL, get_devices_cb, NULL);
 501 }
 502 </pre>
 503 <h2 class="title"><a name="FUNCTIONS">Functions</a></h2>
 504 <h3 class="function"><span class="info">&nbsp;DEPRECATED&nbsp;</span><a name="cupsAdminCreateWindowsPPD">cupsAdminCreateWindowsPPD</a></h3>
 505 <p class="description">Create the Windows PPD file for a printer.</p>
 506 <p class="code">
 507 char *cupsAdminCreateWindowsPPD (<br>
 508 &nbsp;&nbsp;&nbsp;&nbsp;http_t *http,<br>
 509 &nbsp;&nbsp;&nbsp;&nbsp;const char *dest,<br>
 510 &nbsp;&nbsp;&nbsp;&nbsp;char *buffer,<br>
 511 &nbsp;&nbsp;&nbsp;&nbsp;int bufsize<br>
 512 );</p>
 513 <h4 class="parameters">Parameters</h4>
 514 <dl>
 515 <dt>http</dt>
 516 <dd class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></dd>
 517 <dt>dest</dt>
 518 <dd class="description">Printer or class</dd>
 519 <dt>buffer</dt>
 520 <dd class="description">Filename buffer</dd>
 521 <dt>bufsize</dt>
 522 <dd class="description">Size of filename buffer</dd>
 523 </dl>
 524 <h4 class="returnvalue">Return Value</h4>
 525 <p class="description">PPD file or NULL</p>
 526 <h3 class="function"><span class="info">&nbsp;DEPRECATED&nbsp;</span><a name="cupsAdminExportSamba">cupsAdminExportSamba</a></h3>
 527 <p class="description">Export a printer to Samba.</p>
 528 <p class="code">
 529 int cupsAdminExportSamba (<br>
 530 &nbsp;&nbsp;&nbsp;&nbsp;const char *dest,<br>
 531 &nbsp;&nbsp;&nbsp;&nbsp;const char *ppd,<br>
 532 &nbsp;&nbsp;&nbsp;&nbsp;const char *samba_server,<br>
 533 &nbsp;&nbsp;&nbsp;&nbsp;const char *samba_user,<br>
 534 &nbsp;&nbsp;&nbsp;&nbsp;const char *samba_password,<br>
 535 &nbsp;&nbsp;&nbsp;&nbsp;FILE *logfile<br>
 536 );</p>
 537 <h4 class="parameters">Parameters</h4>
 538 <dl>
 539 <dt>dest</dt>
 540 <dd class="description">Destination to export</dd>
 541 <dt>ppd</dt>
 542 <dd class="description">PPD file</dd>
 543 <dt>samba_server</dt>
 544 <dd class="description">Samba server</dd>
 545 <dt>samba_user</dt>
 546 <dd class="description">Samba username</dd>
 547 <dt>samba_password</dt>
 548 <dd class="description">Samba password</dd>
 549 <dt>logfile</dt>
 550 <dd class="description">Log file, if any</dd>
 551 </dl>
 552 <h4 class="returnvalue">Return Value</h4>
 553 <p class="description">1 on success, 0 on failure</p>
 554 <h3 class="function"><span class="info">&nbsp;CUPS 1.3/OS X 10.5&nbsp;</span><a name="cupsAdminGetServerSettings">cupsAdminGetServerSettings</a></h3>
 555 <p class="description">Get settings from the server.</p>
 556 <p class="code">
 557 int cupsAdminGetServerSettings (<br>
 558 &nbsp;&nbsp;&nbsp;&nbsp;http_t *http,<br>
 559 &nbsp;&nbsp;&nbsp;&nbsp;int *num_settings,<br>
 560 &nbsp;&nbsp;&nbsp;&nbsp;cups_option_t **settings<br>
 561 );</p>
 562 <h4 class="parameters">Parameters</h4>
 563 <dl>
 564 <dt>http</dt>
 565 <dd class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></dd>
 566 <dt>num_settings</dt>
 567 <dd class="description">Number of settings</dd>
 568 <dt>settings</dt>
 569 <dd class="description">Settings</dd>
 570 </dl>
 571 <h4 class="returnvalue">Return Value</h4>
 572 <p class="description">1 on success, 0 on failure</p>
 573 <h4 class="discussion">Discussion</h4>
 574 <p class="discussion">The returned settings should be freed with cupsFreeOptions() when
 575 you are done with them.
 576
 577 </p>
 578 <h3 class="function"><span class="info">&nbsp;CUPS 1.3/OS X 10.5&nbsp;</span><a name="cupsAdminSetServerSettings">cupsAdminSetServerSettings</a></h3>
 579 <p class="description">Set settings on the server.</p>
 580 <p class="code">
 581 int cupsAdminSetServerSettings (<br>
 582 &nbsp;&nbsp;&nbsp;&nbsp;http_t *http,<br>
 583 &nbsp;&nbsp;&nbsp;&nbsp;int num_settings,<br>
 584 &nbsp;&nbsp;&nbsp;&nbsp;cups_option_t *settings<br>
 585 );</p>
 586 <h4 class="parameters">Parameters</h4>
 587 <dl>
 588 <dt>http</dt>
 589 <dd class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></dd>
 590 <dt>num_settings</dt>
 591 <dd class="description">Number of settings</dd>
 592 <dt>settings</dt>
 593 <dd class="description">Settings</dd>
 594 </dl>
 595 <h4 class="returnvalue">Return Value</h4>
 596 <p class="description">1 on success, 0 on failure</p>
 597 <h3 class="function"><span class="info">&nbsp;CUPS 1.4/OS X 10.6&nbsp;</span><a name="cupsGetDevices">cupsGetDevices</a></h3>
 598 <p class="description">Get available printer devices.</p>
 599 <p class="code">
 600 ipp_status_t cupsGetDevices (<br>
 601 &nbsp;&nbsp;&nbsp;&nbsp;http_t *http,<br>
 602 &nbsp;&nbsp;&nbsp;&nbsp;int timeout,<br>
 603 &nbsp;&nbsp;&nbsp;&nbsp;const char *include_schemes,<br>
 604 &nbsp;&nbsp;&nbsp;&nbsp;const char *exclude_schemes,<br>
 605 &nbsp;&nbsp;&nbsp;&nbsp;<a href="#cups_device_cb_t">cups_device_cb_t</a> callback,<br>
 606 &nbsp;&nbsp;&nbsp;&nbsp;void *user_data<br>
 607 );</p>
 608 <h4 class="parameters">Parameters</h4>
 609 <dl>
 610 <dt>http</dt>
 611 <dd class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></dd>
 612 <dt>timeout</dt>
 613 <dd class="description">Timeout in seconds or <code>CUPS_TIMEOUT_DEFAULT</code></dd>
 614 <dt>include_schemes</dt>
 615 <dd class="description">Comma-separated URI schemes to include or <code>CUPS_INCLUDE_ALL</code></dd>
 616 <dt>exclude_schemes</dt>
 617 <dd class="description">Comma-separated URI schemes to exclude or <code>CUPS_EXCLUDE_NONE</code></dd>
 618 <dt>callback</dt>
 619 <dd class="description">Callback function</dd>
 620 <dt>user_data</dt>
 621 <dd class="description">User data pointer</dd>
 622 </dl>
 623 <h4 class="returnvalue">Return Value</h4>
 624 <p class="description">Request status - <code>IPP_OK</code> on success.</p>
 625 <h4 class="discussion">Discussion</h4>
 626 <p class="discussion">This function sends a CUPS-Get-Devices request and streams the discovered
 627 devices to the specified callback function. The &quot;timeout&quot; parameter controls
 628 how long the request lasts, while the &quot;include_schemes&quot; and &quot;exclude_schemes&quot;
 629 parameters provide comma-delimited lists of backends to include or omit from
 630 the request respectively.
 631
 632 </p>
 633 <h2 class="title"><a name="TYPES">Data Types</a></h2>
 634 <h3 class="typedef"><span class="info">&nbsp;CUPS 1.4/OS X 10.6&nbsp;</span><a name="cups_device_cb_t">cups_device_cb_t</a></h3>
 635 <p class="description">Device callback
 636 </p>
 637 <p class="code">
 638 typedef void (*cups_device_cb_t)(const char *device_class, const char *device_id, const char *device_info, const char *device_make_and_model, const char *device_uri, const char *device_location, void *user_data);
 639 </p>
 640 </div>
 641 </body>
 642 </html>