doc/help/api-admin.html

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 441   <body>
 442 <!--
 443   Administrative API header for CUPS.
 444
 445   Copyright 2016 by Apple Inc.
 446
 447   These coded instructions, statements, and computer programs are the
 448   property of Apple Inc. and are protected by Federal copyright
 449   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
 450   which should have been included with this file.  If this file is
 451   file is missing or damaged, see the license at "http://www.cups.org/".
 452 -->
 453
 454 <h1 class='title'>Administrative APIs</h1>
 455
 456 <div class='summary'><table summary='General Information'>
 457 <thead>
 458 <tr>
 459         <th>Header</th>
 460         <th>cups/adminutil.h</th>
 461 </tr>
 462 </thead>
 463 <tbody>
 464 <tr>
 465         <th>Library</th>
 466         <td>-lcups</td>
 467 </tr>
 468 <tr>
 469         <th>See Also</th>
 470         <td>Programming: <a href='api-overview.html' target='_top'>Introduction to CUPS Programming</a><br>
 471         Programming: <a href='api-cups.html' target='_top'>CUPS API</a><br>
 472         Programming: <a href='api-httpipp.html' target='_top'>HTTP and IPP APIs</a></td>
 473 </tr>
 474 </tbody>
 475 </table></div>
 476     <div class="contents">
 477       <h2 class="title">Contents</h2>
 478       <ul class="contents">
 479         <li><a href="#OVERVIEW">Overview</a><ul class="subcontents">
 480           <li><a href="#SETTINGS">Scheduler Settings</a></li>
 481           <li><a href="#DEVICES">Devices</a></li>
 482         </ul></li>
 483         <li><a href="#FUNCTIONS">Functions</a><ul class="subcontents">
 484           <li><a href="#cupsAdminCreateWindowsPPD">cupsAdminCreateWindowsPPD</a></li>
 485           <li><a href="#cupsAdminExportSamba">cupsAdminExportSamba</a></li>
 486           <li><a href="#cupsAdminGetServerSettings">cupsAdminGetServerSettings</a></li>
 487           <li><a href="#cupsAdminSetServerSettings">cupsAdminSetServerSettings</a></li>
 488           <li><a href="#cupsGetDevices">cupsGetDevices</a></li>
 489         </ul></li>
 490         <li><a href="#TYPES">Data Types</a><ul class="subcontents">
 491           <li><a href="#cups_device_cb_t">cups_device_cb_t</a></li>
 492         </ul></li>
 493       </ul>
 494     </div>
 495     <div class="body">
 496 <!--
 497   Administrative API documentation for CUPS.
 498
 499   Copyright 2016 by Apple Inc.
 500
 501   These coded instructions, statements, and computer programs are the
 502   property of Apple Inc. and are protected by Federal copyright
 503   law.  Distribution and use rights are outlined in the file "LICENSE.txt"
 504   which should have been included with this file.  If this file is
 505   file is missing or damaged, see the license at "http://www.cups.org/".
 506 -->
 507
 508 <h2 class="title"><a name="OVERVIEW">Overview</a></h2>
 509
 510 <p>The administrative APIs provide convenience functions to perform certain administrative functions with the CUPS scheduler.</p>
 511
 512 <blockquote><b>Note:<b>
 513   <p>Administrative functions normally require administrative privileges to execute and must not be used in ordinary user applications!</p>
 514 </blockquote>
 515
 516 <h3><a name="SETTINGS">Scheduler Settings</a></h3>
 517
 518 <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>
 519
 520 <ul>
 521   <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>
 522   <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>
 523   <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>
 524   <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>
 525   <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>
 526 </ul>
 527
 528 <blockquote><b>Note:</b>
 529   <p>Changing settings will restart the CUPS scheduler.</p>
 530   <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>
 531 </blockquote>
 532
 533 <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>
 534
 535 <pre class="example">
 536 #include &lt;cups/cups.h&gt;
 537 #include &lt;cups/adminutil.h&gt;
 538
 539 void
 540 enable_web_interface(void)
 541 {
 542   int num_settings = 0;           /* Number of settings */
 543   cups_option_t *settings = NULL; /* Settings */
 544
 545
 546   if (!<a href="#cupsAdminGetServerSettings">cupsAdminGetServerSettings</a>(CUPS_HTTP_DEFAULT, &amp;num_settings, &amp;settings))
 547   {
 548     fprintf(stderr, "ERROR: Unable to get server settings: %s\n", cupsLastErrorString());
 549     return;
 550   }
 551
 552   num_settings = <a href="api-cups.html#cupsAddOption">cupsAddOption</a>("WebInterface", "Yes", num_settings, &amp;settings);
 553
 554   if (!<a href="#cupsAdminSetServerSettings">cupsAdminSetServerSettings</a>(CUPS_HTTP_DEFAULT, num_settings, settings))
 555   {
 556     fprintf(stderr, "ERROR: Unable to set server settings: %s\n", cupsLastErrorString());
 557   }
 558
 559   <a href="api-cups.html#cupsFreeOptions">cupsFreeOptions</a>(num_settings, settings);
 560 }
 561 </pre>
 562
 563 <h3><a name="DEVICES">Devices</a></h3>
 564
 565 <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>
 566
 567 <pre class="example">
 568 #include &lt;cups/cups.h&gt;
 569 #include &lt;cups/adminutil.h&gt;
 570
 571
 572 void
 573 get_devices_cb(
 574     const char *device_class,           /* I - Class */
 575     const char *device_id,              /* I - 1284 device ID */
 576     const char *device_info,            /* I - Description */
 577     const char *device_make_and_model,  /* I - Make and model */
 578     const char *device_uri,             /* I - Device URI */
 579     const char *device_location,        /* I - Location */
 580     void       *user_data)              /* I - User data */
 581 {
 582   puts(device_uri);
 583 }
 584
 585
 586 void
 587 show_devices(void)
 588 {
 589   <a href="#cupsGetDevices">cupsGetDevices</a>(CUPS_HTTP_DEFAULT, 30, NULL, NULL, get_devices_cb, NULL);
 590 }
 591 </pre>
 592       <h2 class="title"><a id="FUNCTIONS">Functions</a></h2>
 593 <h3 class="function"><span class="info">&#160;DEPRECATED&#160;</span><a id="cupsAdminCreateWindowsPPD">cupsAdminCreateWindowsPPD</a></h3>
 594         <p class="description">Create the Windows PPD file for a printer.</p>
 595 <p class="code">
 596 char *cupsAdminCreateWindowsPPD(http_t *http, const char *dest, char *buffer, int bufsize);</p>
 597 <h4 class="parameters">Parameters</h4>
 598 <table class="list"><tbody>
 599 <tr><th>http</th>
 600         <td class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></td></tr>
 601 <tr><th>dest</th>
 602         <td class="description">Printer or class</td></tr>
 603 <tr><th>buffer</th>
 604         <td class="description">Filename buffer</td></tr>
 605 <tr><th>bufsize</th>
 606         <td class="description">Size of filename buffer</td></tr>
 607 </tbody></table>
 608 <h4 class="returnvalue">Return Value</h4>
 609         <p class="description">PPD file or NULL</p>
 610 <h3 class="function"><span class="info">&#160;DEPRECATED&#160;</span><a id="cupsAdminExportSamba">cupsAdminExportSamba</a></h3>
 611         <p class="description">Export a printer to Samba.</p>
 612 <p class="code">
 613 int cupsAdminExportSamba(const char *dest, const char *ppd, const char *samba_server, const char *samba_user, const char *samba_password, FILE *logfile);</p>
 614 <h4 class="parameters">Parameters</h4>
 615 <table class="list"><tbody>
 616 <tr><th>dest</th>
 617         <td class="description">Destination to export</td></tr>
 618 <tr><th>ppd</th>
 619         <td class="description">PPD file</td></tr>
 620 <tr><th>samba_server</th>
 621         <td class="description">Samba server</td></tr>
 622 <tr><th>samba_user</th>
 623         <td class="description">Samba username</td></tr>
 624 <tr><th>samba_password</th>
 625         <td class="description">Samba password</td></tr>
 626 <tr><th>logfile</th>
 627         <td class="description">Log file, if any</td></tr>
 628 </tbody></table>
 629 <h4 class="returnvalue">Return Value</h4>
 630         <p class="description">1 on success, 0 on failure</p>
 631 <h3 class="function"><span class="info">&#160;CUPS 1.3/macOS 10.5&#160;</span><a id="cupsAdminGetServerSettings">cupsAdminGetServerSettings</a></h3>
 632         <p class="description">Get settings from the server.</p>
 633 <p class="code">
 634 int cupsAdminGetServerSettings(http_t *http, int *num_settings, cups_option_t **settings);</p>
 635 <h4 class="parameters">Parameters</h4>
 636 <table class="list"><tbody>
 637 <tr><th>http</th>
 638         <td class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></td></tr>
 639 <tr><th>num_settings</th>
 640         <td class="description">Number of settings</td></tr>
 641 <tr><th>settings</th>
 642         <td class="description">Settings</td></tr>
 643 </tbody></table>
 644 <h4 class="returnvalue">Return Value</h4>
 645         <p class="description">1 on success, 0 on failure</p>
 646 <h4 class="discussion">Discussion</h4>
 647         <p class="discussion">The returned settings should be freed with cupsFreeOptions() when
 648 you are done with them.
 649
 650 </p>
 651 <h3 class="function"><span class="info">&#160;CUPS 1.3/macOS 10.5&#160;</span><a id="cupsAdminSetServerSettings">cupsAdminSetServerSettings</a></h3>
 652         <p class="description">Set settings on the server.</p>
 653 <p class="code">
 654 int cupsAdminSetServerSettings(http_t *http, int num_settings, cups_option_t *settings);</p>
 655 <h4 class="parameters">Parameters</h4>
 656 <table class="list"><tbody>
 657 <tr><th>http</th>
 658         <td class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></td></tr>
 659 <tr><th>num_settings</th>
 660         <td class="description">Number of settings</td></tr>
 661 <tr><th>settings</th>
 662         <td class="description">Settings</td></tr>
 663 </tbody></table>
 664 <h4 class="returnvalue">Return Value</h4>
 665         <p class="description">1 on success, 0 on failure</p>
 666 <h3 class="function"><span class="info">&#160;CUPS 1.4/macOS 10.6&#160;</span><a id="cupsGetDevices">cupsGetDevices</a></h3>
 667         <p class="description">Get available printer devices.</p>
 668 <p class="code">
 669 ipp_status_t cupsGetDevices(http_t *http, int timeout, const char *include_schemes, const char *exclude_schemes, <a href="#cups_device_cb_t">cups_device_cb_t</a> callback, void *user_data);</p>
 670 <h4 class="parameters">Parameters</h4>
 671 <table class="list"><tbody>
 672 <tr><th>http</th>
 673         <td class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></td></tr>
 674 <tr><th>timeout</th>
 675         <td class="description">Timeout in seconds or <code>CUPS_TIMEOUT_DEFAULT</code></td></tr>
 676 <tr><th>include_schemes</th>
 677         <td class="description">Comma-separated URI schemes to include or <code>CUPS_INCLUDE_ALL</code></td></tr>
 678 <tr><th>exclude_schemes</th>
 679         <td class="description">Comma-separated URI schemes to exclude or <code>CUPS_EXCLUDE_NONE</code></td></tr>
 680 <tr><th>callback</th>
 681         <td class="description">Callback function</td></tr>
 682 <tr><th>user_data</th>
 683         <td class="description">User data pointer</td></tr>
 684 </tbody></table>
 685 <h4 class="returnvalue">Return Value</h4>
 686         <p class="description">Request status - <code>IPP_OK</code> on success.</p>
 687 <h4 class="discussion">Discussion</h4>
 688         <p class="discussion">This function sends a CUPS-Get-Devices request and streams the discovered
 689 devices to the specified callback function. The &quot;timeout&quot; parameter controls
 690 how long the request lasts, while the &quot;include_schemes&quot; and &quot;exclude_schemes&quot;
 691 parameters provide comma-delimited lists of backends to include or omit from
 692 the request respectively.
 693
 694 </p>
 695       <h2 class="title"><a id="TYPES">Data Types</a></h2>
 696       <h3 class="typedef"><a id="cups_device_cb_t"><span class="info">&#160;CUPS 1.4/macOS 10.6&#160;</span>cups_device_cb_t</a></h3>
 697         <p class="description">Device callback
 698 </p>
 699       <p class="code">
 700 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);
 701 </p>
 702     </div>
 703   </body>
 704 </html>