<p>CUPS implements <ahref="http://ftp.pwg.org/pub/pwg/standards/std-ipp20-20151030-5100.12.pdf">IPP/2.1</a> and the operations and attributes defined in the following specifications:</p>
<ul>
<li><ahref="http://ftp.pwg.org/pub/pwg/candidates/cs-ippjobprinterext10-20101030-5100.11.pdf">PWG 5100.11: IPP Job and Printer Extensions - Set 2 (JPS2)</a> (all operations plus the "job-creation-attributes-supported", "job-ids", "job-password", "job-password-encryption", "media-col-database", and "which-jobs" attributes)</li>
<li><ahref="http://ftp.pwg.org/pub/pwg/candidates/cs-ippjobprinterext3v10-20120727-5100.13.pdf">PWG 5100.13: IPP Job and Printer Extensions - Set 3 (JPS3)</a> (all operations/attributes required for IPP Everywhere except "printer-geo-location" and "printer-icc-profiles")</li>
<li><ahref="http://ftp.pwg.org/pub/pwg/candidates/cs-ippeve10-20130128-5100.14.pdf">PWG 5100.14: IPP Everywhere</a> (conforming to the Client and most of the Printer requirements)</li>
<p>So a typical printer URI would be "ipp://foo.example.com/printers/LaserJet". In addition, the CUPS scheduler also supports (when enabled) normal browser access via "http://foo.example.com:port/" and "https://foo.example.com:port/".</p>
<p>The following sections describe the operations supported by CUPS. In the interest of brevity, operations which use only the standard IPP attributes are not described.
<p>The Cancel-Job operation (0x0008) cancels the specified job. CUPS 1.4 added support for the <tt>purge-job (boolean)</tt> operation attribute that (if 'true') removes all history and document files for the job as well.</p>
<p>The Purge-Jobs operation (0x0012) cancels all of the jobs on a given destination and optionally removes all history and document files for the jobs as well. CUPS 1.2 added support for the <tt>purge-job (boolean)</tt> operation attribute that (if 'false') retains all history and document files for the canceled jobs.</p>
<blockquote><b>Note:</b>
<p>The Cancel-Jobs and Cancel-My-Jobs operations should be used instead of Purge-Jobs.</p>
<p>The Create-Printer-Subscription operation (0x0016) creates a subscription for printer or server event notifications. CUPS provides several additional events in addition to the standard events in the IPP notifications specification. CUPS adds the following <tt>notify-events (1setOf type2 keyword)</tt> values:<p>
<ul>
<li><tt>printer-added</tt> - Get notified whenever a printer or class is added</li>
<li><tt>printer-deleted</tt> - Get notified whenever a printer or class is deleted</li>
<li><tt>printer-modified</tt> - Get notified whenever a printer or class is modified</li>
<li><tt>server-audit</tt> - Get notified when a security condition occurs</li>
<li><tt>server-restarted</tt> - Get notified when the server is restarted</li>
<li><tt>server-started</tt> - Get notified when the server is started</li>
<li><tt>server-stopped</tt> - Get notified when the server is stopped</li>
<p>The CUPS-Get-Default operation (0x4001) returns the default printer URI and attributes.
<h4>CUPS-Get-Default Request</h4>
<p>The following groups of attributes are supplied as part of the CUPS-Get-Default request:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.1 of the IPP Model and Semantics document.
<dt>"requested-attributes" (1setOf keyword):
<dd>The client OPTIONALLY supplies a set of attribute names and/or attribute group names in whose values the requester is interested. If the client omits this attribute, the server responds as if this attribute had been supplied with a value of 'all'.
</dl>
<h4>CUPS-Get-Default Response</h4>
<p>The following groups of attributes are send as part of the CUPS-Get-Default Response:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.2 of the IPP Model and Semantics document.
<dt>Status Message:
<dd>The standard response status message.
</dl>
<p>Group 2: Printer Object Attributes
<dl>
<dt>The set of requested attributes and their current values.
<p>The CUPS-Get-Printers operation (0x4002) returns the printer attributes for every printer known to the system. This may include printers that are not served directly by the server.
<h4>CUPS-Get-Printers Request</h4>
<p>The following groups of attributes are supplied as part of the CUPS-Get-Printers request:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.1 of the IPP Model and Semantics document.
<dd>The client OPTIONALLY supplies a printer type mask enumeration to select which bits are used in the "printer-type" attribute.
<dt>"requested-attributes" (1setOf keyword):
<dd>The client OPTIONALLY supplies a set of attribute names and/or attribute group names in whose values the requester is interested. If the client omits this attribute, the server responds as if this attribute had been supplied with a value of 'all'.
<dd>The client OPTIONALLY supplies one or two banner page names that are printed before and after files in a job. The reserved name "none" is used to specify that no banner page should be printed.
<dt>"device-uri" (uri):
<dd>The client OPTIONALLY supplies a device URI for the specified printer.
<dt>"port-monitor" (name(127)):
<dd>The client OPTIONALLY supplies a port monitor name for the specified printer.
<dt>"ppd-name" (name(255)):
<dd>The client OPTIONALLY supplies a PPD name for the specified printer.
<dt>"printer-is-accepting-jobs" (boolean):
<dd>The client OPTIONALLY supplies this boolean attribute indicating whether the printer object should accept new jobs.
<dt>"printer-info" (text(127)):
<dd>The client OPTIONALLY supplies this attribute indicating the printer information string.
<dt>"printer-location" (text(127)):
<dd>The client OPTIONALLY supplies this attribute indicating a textual location of the printer.
<dt>"printer-more-info" (uri):
<dd>The client OPTIONALLY supplies this attribute indicating a URI for additional printer information.
<dt>"printer-state" (type2 enum):
<dd>The client OPTIONALLY supplies this attribute indicating the initial/current state of the printer. Only the 'idle(3)' and 'stopped(5)' enumerations are recognized.
<dt>"printer-state-message" (text(MAX)):
<dd>The client OPTIONALLY supplies this attribute indicating a textual reason for the current printer state.
<dd>The client OPTIONALLY supplies one of these attributes to specify an access control list for incoming print jobs. To allow all users access to a printer, use the delete tag for the attribute value.
</dl>
<p>The CUPS-Add-Modify-Printer request can optionally be followed by a PPD file to be used for the printer. The "ppd-name" attribute overrides any file that is attached to the end of the request with a local CUPS PPD file.
<h4>CUPS-Add-Modify-Printer Response</h4>
<p>The following groups of attributes are send as part of the
CUPS-Add-Modify-Printer Response:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.2 of the IPP Model and Semantics document.
<p>The CUPS-Get-Classes operation (0x4005) returns the printer attributes for every printer class known to the system. This may include printer classes that are not served directly by the server.
<h4>CUPS-Get-Classes Request</h4>
<p>The following groups of attributes are supplied as part of the CUPS-Get-Classes request:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.1 of the IPP Model and Semantics document.
<dd>The client OPTIONALLY supplies a printer type mask enumeration to select which bits are used in the "printer-type" attribute.
<dt>"requested-attributes" (1setOf keyword):
<dd>The client OPTIONALLY supplies a set of attribute names and/or attribute group names in whose values the requester is interested. If the client omits this attribute, the server responds as if this attribute had been supplied with a value of 'all'.
<dd>The client OPTIONALLY supplies one or more authentication keywords that are required to communicate with the printer/remote queue.
<dt>"member-uris" (1setof uri):
<dd>The client OPTIONALLY supplies the "member-uris" set specifying the printers and printer classes that are part of the class.
<dt>"printer-is-accepting-jobs" (boolean):
<dd>The client OPTIONALLY supplies this boolean attribute indicating whether the class object should accept new jobs.
<dt>"printer-info" (text(127)):
<dd>The client OPTIONALLY supplies this attribute indicating the printer information string.
<dt>"printer-location" (text(127)):
<dd>The client OPTIONALLY supplies this attribute indicating a textual location of the class.
<dt>"printer-more-info" (uri):
<dd>The client OPTIONALLY supplies this attribute indicating a URI for additional class information.
<dt>"printer-state" (type2 enum):
<dd>The client OPTIONALLY supplies this attribute indicating the initial/current state of the class. Only the 'idle(3)' and 'stopped(5)' enumerations are recognized.
<dt>"printer-state-message" (text(MAX)):
<dd>The client OPTIONALLY supplies this attribute indicating a textual reason for the current class state.
<dd>The client OPTIONALLY supplies one of these attributes to specify an access control list for incoming print jobs. To allow all users access to a class, use the delete tag for the attribute value.
</dl>
<h4>CUPS-Add-Modify-Class Response</h4>
<p>The following groups of attributes are send as part of the CUPS-Add-Modify-Class Response:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.2 of the IPP Model and Semantics document.
<dd>The client OPTIONALLY supplies a set of scheme names that the requestor does not want to discover. If the client omits this attribute, the server responds with devices of all schemes specified by the "include-schemes" attribute.
<dd>The client OPTIONALLY supplies a set of scheme names that the requestor wants to discover. If the client omits this attribute, the server responds with devices of all schemes except those specified by the "exclude-schemes" attribute.
<dt>"limit" (integer (1:MAX)):
<dd>The client OPTIONALLY supplies this attribute limiting the number of devices that are returned.
<dt>"requested-attributes" (1setOf keyword):
<dd>The client OPTIONALLY supplies a set of attribute names and/or attribute group names in whose values the requester is interested. If the client omits this attribute, the server responds as if this attribute had been supplied with a value of 'all'.
<dd>The client OPTIONALLY supplies a set of scheme names that the requestor does not want to list. If the client omits this attribute, the server responds with PPDs of all schemes specified by the "include-schemes" attribute.
<dd>The client OPTIONALLY supplies a set of scheme names that the requestor wants to list. If the client omits this attribute, the server responds with PPDs of all schemes except those specified by the "exclude-schemes" attribute.
<dt>"limit" (integer (1:MAX)):
<dd>The client OPTIONALLY supplies this attribute limiting the number of PPDs that are returned.
<dt>"ppd-make" (text(127)):
<dd>The client OPTIONALLY supplies a printer manufacturer to select which PPDs are returned.
<dd>The client OPTIONALLY supplies a driver type to select which PPDs are returned.
<dt>"requested-attributes" (1setOf keyword):
<dd>The client OPTIONALLY supplies a set of attribute names and/or attribute group names in whose values the requester is interested. If the client omits this attribute, the server responds as if this attribute had been supplied with a value of 'all'. Specify "ppd-make" to get a list of manufacturers.
</dl>
<h4>CUPS-Get-PPDs Response</h4>
<p>The following groups of attributes are send as part of the
CUPS-Get-PPDs Response:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.2 of the IPP Model and Semantics document.
<p>The CUPS-Authenticate-Job operation (0x400E) authenticates a print job for printing, releasing the job if it is held. Typically this is used when printing to a remote server. The authentication information is passed in the HTTP request; the HTTP connection is normally encrypted for this type of request.</p>
<h4>CUPS-Authenticate-Job Request</h4>
<p>The following groups of attributes are supplied as part of the CUPS-Authenticate-Job request:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.1 of the IPP Model and Semantics document.
<dt>"printer-uri" (uri) and "job-id" (integer)
<br><i>OR</i>
<br>"job-uri" (uri):
<dd>The client MUST supply a URI for the specified printer and a job ID number, or the job URI.
<dd>The client OPTIONALLY supplies a new job-hold-until value for the job. If specified and not the "no-hold" value, the job is held instead of released for printing.
</dl>
<h4>CUPS-Authenticate-Job Response</h4>
<p>The following groups of attributes are send as part of the CUPS-Authenticate-Job Response:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.2 of the IPP Model and Semantics document.
<p>The CUPS-Get-PPD operation (0x400F) gets a PPD file from the server. The PPD file can be specified using a <tt>ppd-name</tt> returned by <ahref='#CUPS_GET_PPDS'><tt>CUPS-Get-PPDs</tt></a> or using the <tt>printer-uri</tt> for a queue.</p>
<p>If the PPD file is found, <tt>successful-ok</tt> is returned with the PPD file following the response data.</p>
<p>If the PPD file cannot be served by the local server because the <tt>printer-uri</tt> attribute points to an external printer, a <tt>cups-see-other</tt> status is returned with the correct URI to use.</p>
<p>If the PPD file does not exist, <tt>client-error-not-found</tt> is returned.</p>
<h4>CUPS-Get-PPD Request</h4>
<p>The following group of attributes is supplied as part of the CUPS-Get-PPD request:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.1 of the IPP Model and Semantics document.
<dt>"printer-uri" (uri)
<br><i>OR</i>
<br>"ppd-name" (name(255)):
<dd>The client MUST supply a printer URI or PPD name.
</dl>
<h4>CUPS-Get-PPD Response</h4>
<p>The following group of attributes is sent as part of the CUPS-Get-PPD Response:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.2 of the IPP Model and Semantics document.
<dt>Status Message:
<dd>The standard response status message.
<dt>"printer-uri" (uri):
<dd>The printer that provides the actual PPD file when the status code is cups-see-other (0x280).
</dl>
<p>If the status code is <tt>successful-ok</tt>, the PPD file follows the end of the IPP response.</p>
<p>The CUPS-Get-Document operation (0x4027) gets a document file from a job on the server. The document file is specified using the <tt>document-number</tt> and either the <tt>job-uri</tt> or <tt>printer-uri</tt> and <tt>job-id</tt> identifying the job.</p>
<p>If the document file is found, <tt>successful-ok</tt> is returned with the document file following the response data.</p>
<p>If the document file does not exist, <tt>client-error-not-found</tt> is returned.</p>
<p>If the requesting user does not have access to the document file, <tt>client-error-not-authorized</tt> is returned.
<h4>CUPS-Get-Document Request</h4>
<p>The following group of attributes is supplied as part of the CUPS-Get-Document request:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.1 of the IPP Model and Semantics document.
<dt>"printer-uri" (uri) and "job-id" (integer)
<br><i>OR</i>
<br>"job-uri" (uri):
<dd>The client MUST supply a printer URI and job ID or job URI.
<dd>The client MUST supply a document number to retrieve. The <tt>number-of-documents</tt> attribute for the job defines the maximum document number that can be specified. In the case of jobs with banners (<tt>job-sheets</tt> is not "none"), document number 1 will typically contain the start banner and document number N will typically contain the end banner.
<p>The CUPS-Create-Local-Printer operation (0x4028) creates a local (temporary) print queue pointing to a remote IPP Everywhere Printer. The queue will remain until the scheduler idle exits, is restarted, or the system is restarted or shutdown. Temporary print queues can be made permanent by an administrator by setting the "printer-is-shared" attribute to 'true'.</p>
<p>At a minimum, the scheduler requires a name and URI for the Printer to add. When successful, the local "printer-uri" values are returned and may be used by the Client to submit Job Creation Requests, monitor for state changes, and so forth.</p>
<p>If the named printer already exists, the scheduler will reject the request with the 'client-error-not-possible' status code.</p>
<p>Access Rights: The authenticated user performing this operation MUST be a Local User of the system, and the request MUST be made over a local (domain socket or loopback interface) address. Otherwise, the request will be rejected with the 'client-error-forbidden' status code.</p>
<h4>CUPS-Create-Local-Printer Request</h4>
<p>The following group of attributes is supplied as part of the CUPS-Create-Local-Printer request:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.1 of the IPP Model and Semantics document.
</dl>
<p>Group 2: Printer Attributes
<dl>
<dt>"printer-name" (name(127)):
<dd>The Client MUST supply this attribute which provides the name for the new Printer.
<dt>"device-uri" (uri):
<dd>The Client MUST supply this attribute which provides an "ipp" or "ipps" URI pointing to an IPP Everywhere Printer.
<dt>"printer-device-id" (text(1023)):
<dd>The Client OPTIONALLY supplies this attribute which provides the IEEE 1284 device ID for the new Printer.
<dt>"printer-geo-location" (uri):
<dd>The Client OPTIONALLY supplies this attribute which provides the geo-location of the new Printer as a "geo" URI.
<dt>"printer-info" (text(127)):
<dd>The Client OPTIONALLY supplies this attribute which provides the description for the new Printer.
<dt>"printer-location" (text(127)):
<dd>The Client OPTIONALLY supplies this attribute which provides the location of the new Printer.
</dl>
<h4>CUPS-Create-Local-Printer Response</h4>
<p>The following group of attributes is sent as part of the CUPS-Create-Local-Printer Response:
<p>Group 1: Operation Attributes
<dl>
<dt>Natural Language and Character Set:
<dd>The "attributes-charset" and "attributes-natural-language" attributes as described in section 3.1.4.2 of the IPP Model and Semantics document.
<dt>Status Message:
<dd>The standard response status message.
</dl>
<p>Group 2: Printer Attributes
<dl>
<dt>"printer-id" (integer(0:65535)):
<dd>The numeric identifier for the created Printer.
<dt>"printer-is-accepting-jobs" (boolean):
<dd>Whether the created Printer is accepting jobs at the time of the response.
<dt>"printer-state" (type1 enum):
<dd>The state of the created Printer at the time of the response.
<p>Device attributes are returned by the CUPS-Get-Devices operation and enumerate all of the available hardware devices and network protocols that are supported by the server. Device attributes are reported in the printer-attributes-tag group.</p>
<p>The "device-make-and-model" attribute specifies a device identification string provided by the printer connected to the device. If the device or printer does not support identification then this attribute contains the string 'unknown'.
<h4><aname="device-uri">device-uri (uri)</a></h4>
<p>The "device-uri" attribute specifies a unique identifier for the device. The actual format of the "device-uri" string depends on the value of the "device-class" attribute:
<ul>
<li>'file': The "device-uri" will be of the form 'file:///path/to/filename'.
<li>'direct': The "device-uri" will be of the form 'scheme:/dev/filename' or 'scheme://vendor/identifier', where scheme may be 'parallel' or 'usb' in the current implementation.
<li>'serial': The "device-uri" will be of the form 'serial:/dev/filename?baud=value+parity=value+flow=value'. The baud value is the data rate in bits per second; the supported values depend on the underlying hardware. The parity value can be one of "none", "even", or "odd". The flow value can be one of "none", "soft" (XON/XOFF handshaking), "hard" or "rts/cts" (RTS/CTS handshaking), or "dtrdsr" (DTR/DSR handshaking).
<p>The URI returned by CUPS-Get-Devices will contain the maximum baud rate supported by the device and the best type of flow control available ("soft" or "hard").
<li>'network': The "device-uri" will be of the form 'scheme://[username:password@]hostname[:port]/[resource]', where scheme may be "http", "https", "ipp", "lpd", "smb", or "socket" in the current implementation.
<p>The URI returned by CUPS-Get-Devices MAY only contain the scheme name ('scheme'). It is up to the client application to add the appropriate host and other information when adding a new printer.
<p>The URI returned by Get-Printer-Attributes and CUPS-Get-Printers has any username and password information stripped; the information is still stored and used by the server internally to perform any needed authentication.
<p>The "auth-info" attribute specifies the authentication information to use when printing to a remote device. The order and content of each text value is specifed by the <ahref="#auth-info-required">auth-info-required</a> printer attribute.
<p>The "job-hold-until" attribute specifies a hold time. In addition to the standard IPP/1.1 keyword names, CUPS supports name values of the form "HH:MM" and "HH:MM:SS" that specify a hold time. The hold time is in Universal Coordinated Time (UTC) and <i>not</i> in the local time zone. If the specified time is less than the current time, the job is held until the next day.
<p>The "job-media-progress" status attribute specifies the percentage of completion of the current page. It is only valid when the "job-state" attribute has the 'processing(5)' value.</p>
<p>The "job-printer-state-message" status attribute provides the last known value of the "printer-state-message" attribute for the printer that processed (or is processing) the job.</p>
<p>The "job-printer-state-reasons" status attribute provides the last known value of the "printer-state-reasons" attribute for the printer that processed (or is processing) the job.</p>
<p>The "job-sheets" attribute specifies one or two banner files that are printed before and after a job. The reserved value of "none" disables banner printing. The default value is stored in the "job-sheets-default" attribute.
<p>If only one value is supplied, the banner file is printed before the job. If two values are supplied, the first value is used as the starting banner file and the second as the ending banner file.
<p>The "job-originating-host-name" status attribute specifies the host from which the job was queued. The value will be the hostname or IP address of the client depending on whether hostname resolution is enabled. The localhost address (127.0.0.1) is <b>always</b> resolved to the name "localhost".
<p>The "ppd-make" attribute specifies the manufacturer of the printer (the Manufacturer attribute in the PPD file). If the manufacturer is not specified in the PPD file then an educated guess is made using the NickName attribute in the PPD file.
<p>The "ppd-make-and-model" attribute specifies the manufacturer and model name of the PPD file (the NickName attribute in the PPD file). If the make and model is not specified in the PPD file then the ModelName or ShortNickName attributes are used instead.
<p>The "ppd-name" attribute specifies either the PPD filename on the server relative to the model directory or a URI that maps to a specific driver interface in the driver directory. The forward slash (/) is used to delineate directories.
<p>The "ppd-natural-language" attribute specifies the language encoding of the PPD file (the LanguageVersion attribute in the PPD file). If the language is unknown or undefined then "en" (English) is assumed.
<p>The "auth-info-required" attribute specifies the authentication information that is required for printing a job. The following keywords are recognized:</p>
<ul>
<li>'domain': A domain name is required.</li>
<li>'negotiate': Kerberos is required - this keyword can only appear by itself and causes cupsd to collect the UID of the printing user.</li>
<li>'none': No authentication is required - this keyword can only appear by itself.</li>
<li>'password': A password is required.</li>
<li>'username': A username is required. Some protocols (like SMB) prefix the username with the domain, for example "DOMAIN\user".</li>
<p>The "job-k-limit" attribute specifies the maximum number of kilobytes that may be printed by a user, including banner files. The default value of 0 specifies that there is no limit.
<p>The "job-page-limit" attribute specifies the maximum number of pages that may be printed by a user, including banner files. The default value of 0 specifies that there is no limit.
<p>The "job-quota-period" attribute specifies the time period used for quota calculations, in seconds. The default value of 0 specifies that the limits apply to all jobs that have been printed by a user that are still known to the system.
<p>The "marker-change-time" status attribute specifies the "printer-up-time" value when the last change to the marker-colors, marker-levels, marker-message, marker-names, or marker-types attributes was made.</p>
<p>The "marker-colors" status attribute specifies the color(s) for each supply in the printer. It is only available when the driver provides supply levels. The color is either 'none' or one or more hex-encoded sRGB colors of the form '#RRGGBB'.</p>
<p>The "marker-high-levels" status attribute specifies the supply levels that indicate a near-full condition. A value of 100 should be used for supplies that are consumed/emptied, e.g. ink cartridges.</p>
<p>The "marker-levels" status attribute specifies the current supply levels for the printer. It is only available when the driver provides supply levels. A value of -1 indicates the level is unavailable, -2 indicates unknown, and -3 indicates the level is unknown but has not yet reached capacity. Values from 0 to 100 indicate the corresponding percentage.</p>
<p>The "marker-low-levels" status attribute specifies the supply levels that indicate a near-empty condition. A value of 0 should be used for supplies that are filled, e.g. waste ink tanks.</p>
<p>The "marker-message" status attribute provides a human-readable status message for the current supply levels, e.g. "12 pages of ink remaining." It is only available when the driver provides supply levels.</p>
<p>The "marker-names" status attribute specifies the name(s) for each supply in the printer. It is only available when the driver provides supply levels.</p>
<p>The "marker-types" status attribute specifies the type(s) of each supply in the printer. It is only available when the driver provides supply levels. The following (RFC 3805) types are currently supported:</p>
<p>The "printer-commands" attribute specifies the commands that are supported by the CUPS command file filter. The keyword 'none' indicates that no commands are supported.</p>
<p>The "printer-dns-sd-name" attribute specifies the registered DNS-SD service name for the printer. If the printer is not being shared using this protocol, "printer-dns-sd-name" will have the no-value value.</p>
<p>The "printer-id" status attribute provides a unique integer identifying the printer. It is used when only an IP address and integer are provided for identifying a print queue.</p>
<p>The "printer-type" status attribute specifies printer type and capability bits for the printer or class. The default value is computed from internal state information and the PPD file for the printer. The following bits are defined:</p>
<divclass='table'><tablealign='center'border='1'width='80%'summary='Printer Type Bits'>
<thead>
<tr>
<th>Bit</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td>0x00000001</td>
<td>Is a printer class.</td>
</tr>
<tr>
<td>0x00000002</td>
<td>Is a remote destination.</td>
</tr>
<tr>
<td>0x00000004</td>
<td>Can print in black.</td>
</tr>
<tr>
<td>0x00000008</td>
<td>Can print in color.</td>
</tr>
<tr>
<td>0x00000010</td>
<td>Can print on both sides of the page in hardware.</td>
</tr>
<tr>
<td>0x00000020</td>
<td>Can staple output.</td>
</tr>
<tr>
<td>0x00000040</td>
<td>Can do fast copies in hardware.</td>
</tr>
<tr>
<td>0x00000080</td>
<td>Can do fast copy collation in hardware.</td>
</tr>
<tr>
<td>0x00000100</td>
<td>Can punch output.</td>
</tr>
<tr>
<td>0x00000200</td>
<td>Can cover output.</td>
</tr>
<tr>
<td>0x00000400</td>
<td>Can bind output.</td>
</tr>
<tr>
<td>0x00000800</td>
<td>Can sort output.</td>
</tr>
<tr>
<td>0x00001000</td>
<td>Can handle media up to US-Legal/A4.</td>
</tr>
<tr>
<td>0x00002000</td>
<td>Can handle media from US-Legal/A4 to ISO-C/A2.</td>
</tr>
<tr>
<td>0x00004000</td>
<td>Can handle media larger than ISO-C/A2.</td>
</tr>
<tr>
<td>0x00008000</td>
<td>Can handle user-defined media sizes.</td>
</tr>
<tr>
<td>0x00010000</td>
<td>Is an implicit (server-generated) class.</td>
</tr>
<tr>
<td>0x00020000</td>
<td>Is the a default printer on the network.</td>
</tr>
<tr>
<td>0x00040000</td>
<td>Is a facsimile device.</td>
</tr>
<tr>
<td>0x00080000</td>
<td>Is rejecting jobs.</td>
</tr>
<tr>
<td>0x00100000</td>
<td>Delete this queue.</td>
</tr>
<tr>
<td>0x00200000</td>
<td>Queue is not shared.</td>
</tr>
<tr>
<td>0x00400000</td>
<td>Queue requires authentication.</td>
</tr>
<tr>
<td>0x00800000</td>
<td>Queue supports CUPS command files.</td>
</tr>
<tr>
<td>0x01000000</td>
<td>Queue was automatically discovered and added.</td>
</tr>
<tr>
<td>0x02000000</td>
<td>Queue is a scanner with no printing capabilities.</td>
</tr>
<tr>
<td>0x04000000</td>
<td>Queue is a printer with scanning capabilities.</td>
<p>The "printer-type-mask" attribute is used to choose printers or classes with the CUPS-Get-Printers and CUPS-Get-Classes operations. The bits are defined identically to the printer-type attribute and default to all 1's.
<p>The "requesting-user-name-allowed" attribute lists all of the users that are allowed to access a printer or class. Either this attribute or the "requesting-user-name-denied" attribute will be defined, but not both.
<p>The "requesting-user-name-denied" attribute lists all of the users that are not allowed to access a printer or class. Either this attribute or the "requesting-user-name-allowed" attribute will be defined, but not both.
<h3class='title'><aname='CLASS_ATTRIBUTES'>Printer Class Attributes</a></h3>
<p>Printer class attributes are placed in the printer-attributes-tag group.</p>
<h4>member-names (1setof name(127))</h4>
<p>The "member-names" attribute specifies the "printer-name" attributes for each the member printer and class. Each name corresponds to the same element of the "member-uris" attribute.
<h4>member-uris (1setof uri)</h4>
<p>The "member-uris" attribute specifies the "printer-uri-supported" values for each member printer and class. Each URI corresponds to the same element of the "member-names" attribute.