doc/help/api-admin.html

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 451   </head>
 452   <body>
 453 <!--
 454   Administrative API header for CUPS.
 455
 456   Copyright © 2016 by Apple Inc.
 457
 458   Licensed under Apache License v2.0.  See the file "LICENSE" for more
 459   information.
 460 -->
 461
 462 <h1 class='title'>Administrative APIs</h1>
 463
 464 <div class='summary'><table summary='General Information'>
 465 <thead>
 466 <tr>
 467         <th>Header</th>
 468         <th>cups/adminutil.h</th>
 469 </tr>
 470 </thead>
 471 <tbody>
 472 <tr>
 473         <th>Library</th>
 474         <td>-lcups</td>
 475 </tr>
 476 <tr>
 477         <th>See Also</th>
 478         <td>Programming: <a href='api-overview.html' target='_top'>Introduction to CUPS Programming</a><br>
 479         Programming: <a href='api-cups.html' target='_top'>CUPS API</a><br>
 480         Programming: <a href='api-httpipp.html' target='_top'>HTTP and IPP APIs</a></td>
 481 </tr>
 482 </tbody>
 483 </table></div>
 484     <div class="contents">
 485       <h2 class="title">Contents</h2>
 486       <ul class="contents">
 487         <li><a href="#OVERVIEW">Overview</a><ul class="subcontents">
 488           <li><a href="#SETTINGS">Scheduler Settings</a></li>
 489           <li><a href="#DEVICES">Devices</a></li>
 490         </ul></li>
 491         <li><a href="#FUNCTIONS">Functions</a><ul class="subcontents">
 492           <li><a href="#cupsAdminCreateWindowsPPD">cupsAdminCreateWindowsPPD</a></li>
 493           <li><a href="#cupsAdminExportSamba">cupsAdminExportSamba</a></li>
 494           <li><a href="#cupsAdminGetServerSettings">cupsAdminGetServerSettings</a></li>
 495           <li><a href="#cupsAdminSetServerSettings">cupsAdminSetServerSettings</a></li>
 496           <li><a href="#cupsGetDevices">cupsGetDevices</a></li>
 497         </ul></li>
 498         <li><a href="#TYPES">Data Types</a><ul class="subcontents">
 499           <li><a href="#cups_device_cb_t">cups_device_cb_t</a></li>
 500         </ul></li>
 501       </ul>
 502     </div>
 503     <div class="body">
 504 <!--
 505   Administrative API documentation for CUPS.
 506
 507   Copyright © 2016 by Apple Inc.
 508
 509   Licensed under Apache License v2.0.  See the file "LICENSE" for more
 510   information.
 511 -->
 512
 513 <h2 class="title"><a name="OVERVIEW">Overview</a></h2>
 514
 515 <p>The administrative APIs provide convenience functions to perform certain administrative functions with the CUPS scheduler.</p>
 516
 517 <blockquote><b>Note:</b>
 518   <p>Administrative functions normally require administrative privileges to execute and must not be used in ordinary user applications!</p>
 519 </blockquote>
 520
 521 <h3><a name="SETTINGS">Scheduler Settings</a></h3>
 522
 523 <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>
 524
 525 <ul>
 526   <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>
 527   <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>
 528   <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>
 529   <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>
 530   <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>
 531 </ul>
 532
 533 <blockquote><b>Note:</b>
 534   <p>Changing settings will restart the CUPS scheduler.</p>
 535   <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>
 536 </blockquote>
 537
 538 <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>
 539
 540 <pre class="example">
 541 #include &lt;cups/cups.h&gt;
 542 #include &lt;cups/adminutil.h&gt;
 543
 544 void
 545 enable_web_interface(void)
 546 {
 547   int num_settings = 0;           /* Number of settings */
 548   cups_option_t *settings = NULL; /* Settings */
 549
 550
 551   if (!<a href="#cupsAdminGetServerSettings">cupsAdminGetServerSettings</a>(CUPS_HTTP_DEFAULT, &amp;num_settings, &amp;settings))
 552   {
 553     fprintf(stderr, "ERROR: Unable to get server settings: %s\n", cupsLastErrorString());
 554     return;
 555   }
 556
 557   num_settings = <a href="api-cups.html#cupsAddOption">cupsAddOption</a>("WebInterface", "Yes", num_settings, &amp;settings);
 558
 559   if (!<a href="#cupsAdminSetServerSettings">cupsAdminSetServerSettings</a>(CUPS_HTTP_DEFAULT, num_settings, settings))
 560   {
 561     fprintf(stderr, "ERROR: Unable to set server settings: %s\n", cupsLastErrorString());
 562   }
 563
 564   <a href="api-cups.html#cupsFreeOptions">cupsFreeOptions</a>(num_settings, settings);
 565 }
 566 </pre>
 567
 568 <h3><a name="DEVICES">Devices</a></h3>
 569
 570 <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>
 571
 572 <pre class="example">
 573 #include &lt;cups/cups.h&gt;
 574 #include &lt;cups/adminutil.h&gt;
 575
 576
 577 void
 578 get_devices_cb(
 579     const char *device_class,           /* I - Class */
 580     const char *device_id,              /* I - 1284 device ID */
 581     const char *device_info,            /* I - Description */
 582     const char *device_make_and_model,  /* I - Make and model */
 583     const char *device_uri,             /* I - Device URI */
 584     const char *device_location,        /* I - Location */
 585     void       *user_data)              /* I - User data */
 586 {
 587   puts(device_uri);
 588 }
 589
 590
 591 void
 592 show_devices(void)
 593 {
 594   <a href="#cupsGetDevices">cupsGetDevices</a>(CUPS_HTTP_DEFAULT, 30, NULL, NULL, get_devices_cb, NULL);
 595 }
 596 </pre>
 597       <h2 class="title"><a id="FUNCTIONS">Functions</a></h2>
 598 <h3 class="function"><span class="info">&#160;DEPRECATED&#160;</span><a id="cupsAdminCreateWindowsPPD">cupsAdminCreateWindowsPPD</a></h3>
 599         <p class="description">Create the Windows PPD file for a printer.</p>
 600 <p class="code">
 601 char *cupsAdminCreateWindowsPPD(http_t *http, const char *dest, char *buffer, int bufsize);</p>
 602 <h4 class="parameters">Parameters</h4>
 603 <table class="list"><tbody>
 604 <tr><th>http</th>
 605         <td class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></td></tr>
 606 <tr><th>dest</th>
 607         <td class="description">Printer or class</td></tr>
 608 <tr><th>buffer</th>
 609         <td class="description">Filename buffer</td></tr>
 610 <tr><th>bufsize</th>
 611         <td class="description">Size of filename buffer</td></tr>
 612 </tbody></table>
 613 <h4 class="returnvalue">Return Value</h4>
 614         <p class="description">PPD file or NULL</p>
 615 <h3 class="function"><span class="info">&#160;DEPRECATED&#160;</span><a id="cupsAdminExportSamba">cupsAdminExportSamba</a></h3>
 616         <p class="description">Export a printer to Samba.</p>
 617 <p class="code">
 618 int cupsAdminExportSamba(const char *dest, const char *ppd, const char *samba_server, const char *samba_user, const char *samba_password, FILE *logfile);</p>
 619 <h4 class="parameters">Parameters</h4>
 620 <table class="list"><tbody>
 621 <tr><th>dest</th>
 622         <td class="description">Destination to export</td></tr>
 623 <tr><th>ppd</th>
 624         <td class="description">PPD file</td></tr>
 625 <tr><th>samba_server</th>
 626         <td class="description">Samba server</td></tr>
 627 <tr><th>samba_user</th>
 628         <td class="description">Samba username</td></tr>
 629 <tr><th>samba_password</th>
 630         <td class="description">Samba password</td></tr>
 631 <tr><th>logfile</th>
 632         <td class="description">Log file, if any</td></tr>
 633 </tbody></table>
 634 <h4 class="returnvalue">Return Value</h4>
 635         <p class="description">1 on success, 0 on failure</p>
 636 <h3 class="function"><span class="info">&#160;CUPS 1.3/macOS 10.5&#160;</span><a id="cupsAdminGetServerSettings">cupsAdminGetServerSettings</a></h3>
 637         <p class="description">Get settings from the server.</p>
 638 <p class="code">
 639 int cupsAdminGetServerSettings(http_t *http, int *num_settings, cups_option_t **settings);</p>
 640 <h4 class="parameters">Parameters</h4>
 641 <table class="list"><tbody>
 642 <tr><th>http</th>
 643         <td class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></td></tr>
 644 <tr><th>num_settings</th>
 645         <td class="description">Number of settings</td></tr>
 646 <tr><th>settings</th>
 647         <td class="description">Settings</td></tr>
 648 </tbody></table>
 649 <h4 class="returnvalue">Return Value</h4>
 650         <p class="description">1 on success, 0 on failure</p>
 651 <h4 class="discussion">Discussion</h4>
 652         <p class="discussion">The returned settings should be freed with cupsFreeOptions() when
 653 you are done with them.
 654
 655 </p>
 656 <h3 class="function"><span class="info">&#160;CUPS 1.3/macOS 10.5&#160;</span><a id="cupsAdminSetServerSettings">cupsAdminSetServerSettings</a></h3>
 657         <p class="description">Set settings on the server.</p>
 658 <p class="code">
 659 int cupsAdminSetServerSettings(http_t *http, int num_settings, cups_option_t *settings);</p>
 660 <h4 class="parameters">Parameters</h4>
 661 <table class="list"><tbody>
 662 <tr><th>http</th>
 663         <td class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></td></tr>
 664 <tr><th>num_settings</th>
 665         <td class="description">Number of settings</td></tr>
 666 <tr><th>settings</th>
 667         <td class="description">Settings</td></tr>
 668 </tbody></table>
 669 <h4 class="returnvalue">Return Value</h4>
 670         <p class="description">1 on success, 0 on failure</p>
 671 <h3 class="function"><span class="info">&#160;DEPRECATED&#160;</span><a id="cupsGetDevices">cupsGetDevices</a></h3>
 672         <p class="description">Get available printer devices.</p>
 673 <p class="code">
 674 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>
 675 <h4 class="parameters">Parameters</h4>
 676 <table class="list"><tbody>
 677 <tr><th>http</th>
 678         <td class="description">Connection to server or <code>CUPS_HTTP_DEFAULT</code></td></tr>
 679 <tr><th>timeout</th>
 680         <td class="description">Timeout in seconds or <code>CUPS_TIMEOUT_DEFAULT</code></td></tr>
 681 <tr><th>include_schemes</th>
 682         <td class="description">Comma-separated URI schemes to include or <code>CUPS_INCLUDE_ALL</code></td></tr>
 683 <tr><th>exclude_schemes</th>
 684         <td class="description">Comma-separated URI schemes to exclude or <code>CUPS_EXCLUDE_NONE</code></td></tr>
 685 <tr><th>callback</th>
 686         <td class="description">Callback function</td></tr>
 687 <tr><th>user_data</th>
 688         <td class="description">User data pointer</td></tr>
 689 </tbody></table>
 690 <h4 class="returnvalue">Return Value</h4>
 691         <p class="description">Request status - <code>IPP_OK</code> on success.</p>
 692 <h4 class="discussion">Discussion</h4>
 693         <p class="discussion">This function sends a CUPS-Get-Devices request and streams the discovered
 694 devices to the specified callback function. The &quot;timeout&quot; parameter controls
 695 how long the request lasts, while the &quot;include_schemes&quot; and &quot;exclude_schemes&quot;
 696 parameters provide comma-delimited lists of backends to include or omit from
 697 the request respectively.<br>
 698 <br>
 699 This function is deprecated with the IPP printer discovery functionality
 700 being provided by the <a href="#cupsEnumDests"><code>cupsEnumDests</code></a> and @cupsGetDests@ functions.
 701
 702 </p>
 703       <h2 class="title"><a id="TYPES">Data Types</a></h2>
 704       <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>
 705         <p class="description">Device callback
 706 </p>
 707       <p class="code">
 708 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);
 709 </p>
 710     </div>
 711   </body>
 712 </html>