doc/help/ppd-compiler.html

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 330 </head>
 331 <body>
 332 <div class='body'>
 333 <P>This document describes how to use the CUPS PostScript Printer Description
 334 (PPD) file compiler. The PPD compiler generates PPD files from simple text files
 335 that describe the features and capabilities of one or more printers.</P>
 336
 337 <div class='summary'><table summary='General Information'>
 338 <tbody>
 339 <tr>
 340         <th>See Also</th>
 341         <td>Programming: <a href='raster-driver.html'>Developing Raster Printer Drivers</a><br>
 342         Programming: <a href='postscript-driver.html'>Developing PostScript Printer Drivers</a><br>
 343         Programming: <a href='api-filter.html'>Filter and Backend Programming</a><br>
 344         Programming: <a href='api-raster.html'>Raster API</a><br>
 345         References: <a href='ref-ppdcfile.html'>PPD Compiler Driver Information File Reference</a><br>
 346         Specifications: <a href='spec-ppd.html'>CUPS PPD Extensions</a></td>
 347 </tr>
 348 </tbody>
 349 </table></div>
 350 <h2 class="title">Contents</h2>
 351 <ul class="contents">
 352 <ul class="subcontents">
 353 <li><a href="#BASICS">The Basics</a></li>
 354 <li><a href="#DRV">Driver Information Files</a><ul class="subcontents">
 355 <li><a href="#SIMPLE">A Simple Example</a></li>
 356 <li><a href="#GROUPING">Grouping and Inheritance</a></li>
 357 <li><a href="#COLOR">Color Support</a></li>
 358 <li><a href="#OPTIONS">Defining Custom Options and Option Groups</a></li>
 359 <li><a href="#DEFINE">Defining Constants</a></li>
 360 <li><a href="#CONDITIONAL">Conditional Statements</a></li>
 361 <li><a href="#CONSTRAINTS">Defining Constraints</a></li>
 362 </ul></li>
 363 <h2 class='title'><a name='BASICS'>The Basics</a></h2>
 364
 365 <P>The PPD compiler, <a href='man-ppdc.html'><code>ppdc(1)</code></a>, is a
 366 simple command-line tool that takes a single <I>driver information file</I>,
 367 which by convention uses the extension <VAR>.drv</VAR>, and produces one or more
 368 PPD files that may be distributed with your printer drivers for use with CUPS.
 369 For example, you would run the following command to create the English language
 370 PPD files defined by the driver information file <VAR>mydrivers.drv</VAR>:</P>
 371
 372 <pre class='command'>
 373 ppdc mydrivers.drv
 374 </pre>
 375
 376 <P>The PPD files are placed in a subdirectory called
 377 <VAR>ppd</VAR>. The <TT>-d</TT> option is used to put the PPD
 378 files in a different location, for example:</p>
 379
 380 <pre class='command'>
 381 ppdc -d myppds mydrivers.drv
 382 </pre>
 383
 384 <P>places the PPD files in a subdirectory named
 385 <VAR>myppds</VAR>. Finally, use the <TT>-l</TT> option to
 386 specify the language localization for the PPD files that are
 387 created, for example:</P>
 388
 389 <pre class='command'>
 390 ppdc -d myppds/de -l de mydrivers.drv
 391 ppdc -d myppds/en -l en mydrivers.drv
 392 ppdc -d myppds/es -l es mydrivers.drv
 393 ppdc -d myppds/fr -l fr mydrivers.drv
 394 ppdc -d myppds/it -l it mydrivers.drv
 395 </pre>
 396
 397 <P>creates PPD files in German (de), English (en), Spanish (es),
 398 French (fr), and Italian (it) in the corresponding
 399 subdirectories. Specify multiple languages (separated by commas) to produce
 400 "globalized" PPD files:</p>
 401
 402 <pre class='command'>
 403 ppdc -d myppds -l de,en,es,fr,it mydrivers.drv
 404 </pre>
 405
 406
 407 <h2 class='title'><a name='DRV'>Driver Information Files</a></h2>
 408
 409 <P>The driver information files accepted by the PPD compiler are
 410 plain text files that define the various attributes and options
 411 that are included in the PPD files that are generated. A driver
 412 information file can define the information for one or more printers and
 413 their corresponding PPD files.</P>
 414
 415 <p class='example'><a name="LISTING1">Listing 1: "examples/minimum.drv"</a></p>
 416
 417 <pre class='example'>
 418 <I>// Include standard font and media definitions</I>
 419 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 420 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 421
 422 <I>// List the fonts that are supported, in this case all standard fonts...</I>
 423 <a href='ref-ppdcfile.html#Font'>Font</a> *
 424
 425 <I>// Manufacturer, model name, and version</I>
 426 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 427 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 428 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 429
 430 <I>// Each filter provided by the driver...</I>
 431 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 432
 433 <I>// Supported page sizes</I>
 434 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 435 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 436
 437 <I>// Supported resolutions</I>
 438 *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 439
 440 <I>// Specify the name of the PPD file we want to generate...</I>
 441 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 442 </pre>
 443
 444
 445 <h3><a name='SIMPLE'>A Simple Example</a></h3>
 446
 447 <P>The example in <A HREF="#LISTING1">Listing 1</A> shows a driver information
 448 file which defines the minimum required attributes to provide a valid PPD file.
 449 The first part of the file includes standard definition files for fonts and
 450 media sizes:</P>
 451
 452 <pre class='example'>
 453 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 454 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 455 </pre>
 456
 457 <P>The <TT>#include</TT> directive works just like the C/C++ include directive;
 458 files included using the angle brackets (<TT>&lt;filename&gt;</TT>) are found
 459 in any of the standard include directories and files included using quotes
 460 (<TT>"filename"</TT>) are found in the same directory as the source or include
 461 file. The <TT>&lt;font.defs&gt;</TT> include file defines the standard fonts
 462 which are included with GPL Ghostscript and the Apple PDF RIP, while the
 463 <TT>&lt;media.defs&gt;</TT> include file defines the standard media sizes
 464 listed in Appendix B of the Adobe PostScript Printer Description File Format
 465 Specification.</P>
 466
 467 <P>CUPS provides several other standard include files:</P>
 468
 469 <UL>
 470
 471         <LI><TT>&lt;epson.h&gt;</TT> - Defines all of the rastertoepson driver
 472         constants.</LI>
 473
 474         <LI><TT>&lt;escp.h&gt;</TT> - Defines all of the rastertoescpx driver
 475         constants.</LI>
 476
 477         <LI><TT>&lt;hp.h&gt;</TT> - Defines all of the rastertohp driver
 478         constants.</LI>
 479
 480         <LI><TT>&lt;label.h&gt;</TT> - Defines all of the rastertolabel driver
 481         constants.</LI>
 482
 483         <LI><TT>&lt;pcl.h&gt;</TT> - Defines all of the rastertopclx driver
 484         constants.</LI>
 485
 486         <LI><TT>&lt;raster.defs&gt;</TT> - Defines all of the CUPS raster format
 487         constants.</LI>
 488
 489 </UL>
 490
 491 <P>Next we list all of the fonts that are available in the driver; for CUPS
 492 raster drivers, the following line is all that is usually supplied:</P>
 493
 494 <pre class='example'>
 495 <a href='ref-ppdcfile.html#Font'>Font</a> *
 496 </pre>
 497
 498 <P>The <TT>Font</TT> directive specifies the name of a single font or the
 499 asterisk to specify all fonts. For example, you would use the following line to
 500 define an additional bar code font that you are supplying with your printer
 501 driver:</P>
 502
 503 <pre class='example'>
 504 <I>//   name         encoding  version  charset  status</I>
 505 <a href='ref-ppdcfile.html#Font'>Font</a> Barcode-Foo  Special   "(1.0)"  Special  ROM
 506 </pre>
 507
 508 <P>The name of the font is <TT>Barcode-Foo</TT>. Since it is not a standard
 509 text font, the encoding and charset name <TT>Special</TT> is used. The version
 510 number is <TT>1.0</TT> and the status (where the font is located) is
 511 <TT>ROM</TT> to indicate that the font does not need to be embedded in
 512 documents that use the font for this printer.</P>
 513
 514 <P>Third comes the manufacturer, model name, and version number information
 515 strings:</P>
 516
 517 <pre class='example'>
 518 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 519 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 520 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 521 </pre>
 522
 523 <P>These strings are used when the user (or auto-configuration program) selects
 524 the printer driver for a newly connected device.</p>
 525
 526 <P>The list of filters comes after the information strings; for the example in
 527 <A HREF="#LISTING1">Listing 1</A>, we have a single filter that takes CUPS
 528 raster data:</P>
 529
 530 <pre class='example'>
 531 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 532 </pre>
 533
 534 <P>Each filter specified in the driver information file is the equivalent of a
 535 printer driver for that format; if a user submits a print job in a different
 536 format, CUPS figures out the sequence of commands that will produce a supported
 537 format for the least relative cost.</P>
 538
 539 <P>Once we have defined the driver information we specify the supported options.
 540 For the example driver we support a single resolution of 600 dots per inch and
 541 two media sizes, A4 and Letter:</P>
 542
 543 <pre class='example'>
 544 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 545 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 546
 547 *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 548 </pre>
 549
 550 <P>The asterisk in front of the <TT>MediaSize</TT> and <TT>Resolution</TT>
 551 directives specify that those option choices are the default. The
 552 <TT>MediaSize</TT> directive is followed by a media size name which is normally
 553 defined in the <TT>&lt;media.defs&gt;</TT> file and corresponds to a standard
 554 Adobe media size name. If the default media size is <TT>Letter</TT>, the PPD
 555 compiler will override it to be <TT>A4</TT> for non-English localizations for
 556 you automatically.</P>
 557
 558 <P>The <TT>Resolution</TT> directive accepts several values after it as
 559 follows:</P>
 560
 561 <OL>
 562
 563         <LI>Colorspace for this resolution, if any. In the example file, the
 564         colorspace <TT>k</TT> is used which corresponds to black. For printer
 565         drivers that support color printing, this field is usually specified as
 566         "-" for "no change".</LI>
 567
 568         <LI>Bits per color. In the example file, we define 8 bits per color, for
 569         a continuous-tone grayscale output. All versions of CUPS support 1 and
 570         8 bits per color.  CUPS 1.2 and higher (Mac OS X 10.5 and higher) also
 571         supports 16 bits per color.</LI>
 572
 573         <LI>Rows per band. In the example file, we define 0 rows per band to
 574         indicate that our printer driver does not process the page in
 575         bands.</LI>
 576
 577         <LI>Row feed. In the example, we define the feed value to be 0 to
 578         indicate that our printer driver does not interleave the output.</LI>
 579
 580         <LI>Row step. In the example, we define the step value to be 0 to
 581         indicate that our printer driver does not interleave the output. This
 582         value normally indicates the spacing between the nozzles of an inkjet
 583         printer - when combined with the previous two values, it informs the
 584         driver how to stagger the output on the page to produce interleaved
 585         lines on the page for higher-resolution output.</LI>
 586
 587         <LI>Choice name and text. In the example, we define the choice name and
 588         text to be <TT>"600dpi/600 DPI"</TT>. The name and text are separated by
 589         slash (<TT>/</TT>) character; if no text is specified, then the name is
 590         used as the text. The PPD compiler parses the name to determine the
 591         actual resolution; the name can be of the form
 592         <TT><I>RESOLUTION</I>dpi</TT> for resolutions that are equal
 593         horizontally and vertically or <TT><I>HRES</I>x<I>VRES</I>dpi</TT> for
 594         isometric resolutions. Only integer resolution values are supported, so
 595         a resolution name of <TT>300dpi</TT> is valid while <TT>300.1dpi</TT> is
 596         not.</LI>
 597
 598 </OL>
 599
 600 <P>Finally, the <TT>PCFileName</TT> directive specifies that the named PPD file
 601 should be written for the current driver definitions:</P>
 602
 603 <pre class='example'>
 604 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 605 </pre>
 606
 607 <P>The filename follows the directive and <I>must</I> conform to the Adobe
 608 filename requirements in the Adobe Postscript Printer Description File Format
 609 Specification. Specifically, the filename may not exceed 8 characters followed
 610 by the extension <VAR>.ppd</VAR>. The <TT>FileName</TT> directive can be used to
 611 specify longer filenames:</P>
 612
 613 <pre class='example'>
 614 <a href='ref-ppdcfile.html#FileName'>FileName</a> "FooJet 2000"
 615 </pre>
 616
 617
 618 <h3><a name='GROUPING'>Grouping and Inheritance</a></h3>
 619
 620 <P>The previous example created a single PPD file. Driver information files can
 621 also define multiple printers by using the PPD compiler grouping functionality.
 622 Directives are grouped using the curly braces (<TT>{</TT> and <TT>}</TT>) and
 623 every group that uses the <TT>PCFileName</TT> or <TT>FileName</TT> directives
 624 produces a PPD file with that name. <A HREF="#LISTING2">Listing 2</A> shows a
 625 variation of the original example that uses two groups to define two printers
 626 that share the same printer driver filter but provide two different resolution
 627 options.</P>
 628
 629 <p class='example'><a name="LISTING2">Listing 2: "examples/grouping.drv"</a></p>
 630
 631 <pre class='example'>
 632
 633 <I>// Include standard font and media definitions</I>
 634 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 635 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 636
 637 <I>// List the fonts that are supported, in this case all standard fonts...</I>
 638 <a href='ref-ppdcfile.html#Font'>Font</a> *
 639
 640 <I>// Manufacturer and version</I>
 641 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 642 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 643
 644 <I>// Each filter provided by the driver...</I>
 645 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 646
 647 <I>// Supported page sizes</I>
 648 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 649 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 650
 651 {
 652   <I>// Supported resolutions</I>
 653   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 654
 655   <I>// Specify the model name and filename...</I>
 656   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 657   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 658 }
 659
 660 {
 661   <I>// Supported resolutions</I>
 662   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "1200dpi/1200 DPI"
 663
 664   <I>// Specify the model name and filename...</I>
 665   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2001"
 666   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojt2k1.ppd"
 667 }
 668 </pre>
 669
 670 <P>The second example is essentially the same as the first, except that each
 671 printer model is defined inside of a pair of curly braces. For example, the
 672 first printer is defined using:</P>
 673
 674 <pre class='example'>
 675 {
 676   // Supported resolutions
 677   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 678
 679   // Specify the model name and filename...
 680   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 681   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 682 }
 683 </pre>
 684
 685 <P>The printer <I>inherits</I> all of the definitions from the parent group (the
 686 top part of the file) and adds the additional definitions inside the curly
 687 braces for that printer driver. When we define the second group, it also
 688 inherits the same definitions from the parent group but <I>none</I> of the
 689 definitions from the first driver. Groups can be nested to any number of levels
 690 to support variations of similar models without duplication of information.</P>
 691
 692
 693 <h3><a name='COLOR'>Color Support</a></h3>
 694
 695 <P>For printer drivers that support color printing, the
 696 <TT>ColorDevice</TT> and <TT>ColorModel</TT> directives should be
 697 used to tell the printing system that color output is desired
 698 and in what formats. <A HREF="#LISTING3">Listing 3</A> shows a
 699 variation of the previous example which includes a color printer
 700 that supports printing at 300 and 600 DPI.</P>
 701
 702 <P>The key changes are the addition of the <TT>ColorDevice</TT>
 703 directive:</P>
 704
 705 <pre class='example'>
 706 <a href='ref-ppdcfile.html#ColorDevice'>ColorDevice</a> true
 707 </pre>
 708
 709 <P>which tells the printing system that the printer supports
 710 color printing, and the <TT>ColorModel</TT> directives:</P>
 711
 712 <pre class='example'>
 713 <a href='ref-ppdcfile.html#ColorModel'>ColorModel</a> Gray/Grayscale w chunky 0
 714 *<a href='ref-ppdcfile.html#ColorModel'>ColorModel</a> RGB/Color rgb chunky 0
 715 </pre>
 716
 717 <P>which tell the printing system which colorspaces are supported by the printer
 718 driver for color printing. Each of the <TT>ColorModel</TT> directives is
 719 followed by the option name and text (<TT>Gray/Grayscale</TT> and
 720 <TT>RGB/Color</TT>), the colorspace name (<TT>w</TT> and <TT>rgb</TT>), the
 721 color organization (<TT>chunky</TT>), and the compression mode number
 722 (<TT>0</TT>) to be passed to the driver. The option name can be any of the
 723 standard Adobe <TT>ColorModel</TT> names:</P>
 724
 725 <UL>
 726
 727         <LI><TT>Gray</TT> - Grayscale output.
 728
 729         <LI><TT>RGB</TT> - Color output, typically using the RGB
 730         colorspace, but without a separate black channel.
 731
 732         <LI><TT>CMYK</TT> - Color output with a separate black
 733         channel.
 734
 735 </UL>
 736
 737 <P>Custom names can be used, however it is recommended that you use your vendor
 738 prefix for any custom names, for example "fooName".</P>
 739
 740 <P>The colorspace name can be any of the following universally supported
 741 colorspaces:</P>
 742
 743 <UL>
 744         <LI><TT>w</TT> - Luminance</LI>
 745
 746         <LI><TT>rgb</TT> - Red, green, blue</LI>
 747
 748         <LI><TT>k</TT> - Black</LI>
 749
 750         <LI><TT>cmy</TT> - Cyan, magenta, yellow</LI>
 751
 752         <LI><TT>cmyk</TT> - Cyan, magenta, yellow, black</LI>
 753
 754 </UL>
 755
 756 <P>The color organization can be any of the following values:</P>
 757
 758 <UL>
 759
 760         <LI><TT>chunky</TT> - Color values are passed together on a line
 761         as RGB RGB RGB RGB</LI>
 762
 763         <LI><TT>banded</TT> - Color values are passed separately
 764         on a line as RRRR GGGG BBBB; not supported by the Apple
 765         RIP filters</LI>
 766
 767         <LI><TT>planar</TT> - Color values are passed separately
 768         on a page as RRRR RRRR RRRR ... GGGG GGGG GGGG ... BBBB
 769         BBBB BBBB; not supported by the Apple RIP filters</LI>
 770
 771 </UL>
 772
 773 <P>The compression mode value is passed to the driver in the
 774 <TT>cupsCompression</TT> attribute. It is traditionally used to select an
 775 appropriate compression mode for the color model but can be used for any
 776 purpose, such as specifying a photo mode vs. standard mode.</P>
 777
 778 <p class='example'><a name="LISTING3">Listing 3: "examples/color.drv"</a></p>
 779
 780 <pre class='example'>
 781
 782 <I>// Include standard font and media definitions</I>
 783 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 784 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 785
 786 <I>// List the fonts that are supported, in this case all standard fonts...</I>
 787 <a href='ref-ppdcfile.html#Font'>Font</a> *
 788
 789 <I>// Manufacturer and version</I>
 790 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 791 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 792
 793 <I>// Each filter provided by the driver...</I>
 794 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 795
 796 <I>// Supported page sizes</I>
 797 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 798 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 799
 800 {
 801   <I>// Supported resolutions</I>
 802   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 803
 804   <I>// Specify the model name and filename...</I>
 805   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 806   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 807 }
 808
 809 {
 810   <I>// Supports color printing</I>
 811   <a href='ref-ppdcfile.html#ColorDevice'>ColorDevice</a> true
 812
 813   <I>// Supported colorspaces</I>
 814   <a href='ref-ppdcfile.html#ColorModel'>ColorModel</a> Gray/Grayscale w chunky 0
 815   *<a href='ref-ppdcfile.html#ColorModel'>ColorModel</a> RGB/Color rgb chunky 0
 816
 817   <I>// Supported resolutions</I>
 818   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> - 8 0 0 0 "300dpi/300 DPI"
 819   <a href='ref-ppdcfile.html#Resolution'>Resolution</a> - 8 0 0 0 "600dpi/600 DPI"
 820
 821   <I>// Specify the model name and filename...</I>
 822   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet Color"
 823   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojetco.ppd"
 824 }
 825 </pre>
 826
 827
 828 <h3><a name='OPTIONS'>Defining Custom Options and Option Groups</a></h3>
 829
 830 <P>The <TT>Group</TT>, <TT>Option</TT>, and <TT>Choice</TT>
 831 directives are used to define or select a group, option, or
 832 choice. <A HREF="#LISTING4">Listing 4</A> shows a variation of
 833 the first example that provides two custom options in a group
 834 named "Footasm".</P>
 835
 836 <p class='example'><a name="LISTING4">Listing 4: "examples/custom.drv"</a></p>
 837
 838 <pre class='example'>
 839
 840 <I>// Include standard font and media definitions</I>
 841 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 842 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 843
 844 <I>// List the fonts that are supported, in this case all standard fonts...</I>
 845 <a href='ref-ppdcfile.html#Font'>Font</a> *
 846
 847 <I>// Manufacturer, model name, and version</I>
 848 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 849 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 850 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 851
 852 <I>// Each filter provided by the driver...</I>
 853 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 854
 855 <I>// Supported page sizes</I>
 856 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 857 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 858
 859 <I>// Supported resolutions</I>
 860 *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 861
 862 <I>// Option Group</I>
 863 <a href='ref-ppdcfile.html#Group'>Group</a> "Footasm"
 864
 865   <I>// Boolean option</I>
 866   <a href='ref-ppdcfile.html#Option'>Option</a> "fooEnhance/Resolution Enhancement" Boolean AnySetup 10
 867     *<a href='ref-ppdcfile.html#Choice'>Choice</a> True/Yes "&lt;&lt;/cupsCompression 1&gt;&gt;setpagedevice"
 868     <a href='ref-ppdcfile.html#Choice'>Choice</a> False/No "&lt;&lt;/cupsCompression 0&gt;&gt;setpagedevice"
 869
 870   <I>// Multiple choice option</I>
 871   <a href='ref-ppdcfile.html#Option'>Option</a> "fooOutputType/Output Quality" PickOne AnySetup 10
 872     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "Auto/Automatic Selection"
 873             "&lt;&lt;/OutputType(Auto)&gt;&gt;setpagedevice""
 874     <a href='ref-ppdcfile.html#Choice'>Choice</a> "Text/Optimize for Text"
 875             "&lt;&lt;/OutputType(Text)&gt;&gt;setpagedevice""
 876     <a href='ref-ppdcfile.html#Choice'>Choice</a> "Graph/Optimize for Graphics"
 877             "&lt;&lt;/OutputType(Graph)&gt;&gt;setpagedevice""
 878     <a href='ref-ppdcfile.html#Choice'>Choice</a> "Photo/Optimize for Photos"
 879             "&lt;&lt;/OutputType(Photo)&gt;&gt;setpagedevice""
 880
 881 <I>// Specify the name of the PPD file we want to generate...</I>
 882 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 883 </pre>
 884
 885 <P>The custom group is introduced by the <TT>Group</TT>
 886 directive which is followed by the name and optionally text for
 887 the user:</P>
 888
 889 <pre class='example'>
 890 <a href='ref-ppdcfile.html#Group'>Group</a> "Footasm/Footastic Options"
 891 </pre>
 892
 893 <P>The group name must conform to the PPD specification and
 894 cannot exceed 40 characters in length. If you specify user text,
 895 it cannot exceed 80 characters in length. The groups
 896 <TT>General</TT>, <TT>Extra</TT>, and
 897 <TT>InstallableOptions</TT> are predefined by CUPS; the general
 898 and extra groups are filled by the UI options defined by the PPD
 899 specification. The <TT>InstallableOptions</TT> group is reserved
 900 for options that define whether accessories for the printer
 901 (duplexer unit, finisher, stapler, etc.) are installed.</P>
 902
 903 <P>Once the group is specified, the <TT>Option</TT> directive is
 904 used to introduce a new option:</P>
 905
 906 <pre class='example'>
 907 <a href='ref-ppdcfile.html#Option'>Option</a> "fooEnhance/Resolution Enhancement" Boolean AnySetup 10
 908 </pre>
 909
 910 <P>The directive is followed by the name of the option and any
 911 optional user text, the option type, the PostScript document group, and
 912 the sort order number. The option name must conform to the PPD specification
 913 and cannot exceed 40 characters in length. If you specify user text, it
 914 cannot exceed 80 characters in length.</P>
 915
 916 <P>The option type can be <TT>Boolean</TT> for true/false
 917 selections, <TT>PickOne</TT> for picking one of many choices, or
 918 <TT>PickMany</TT> for picking zero or more choices. Boolean
 919 options can have at most two choices with the names
 920 <TT>False</TT> and <TT>True</TT>. Pick options can have any
 921 number of choices, although for Windows compatibility reasons
 922 the number of choices should not exceed 255.</P>
 923
 924 <P>The PostScript document group is typically <TT>AnySetup</TT>,
 925 meaning that the option can be introduced at any point in the
 926 PostScript document. Other values include <TT>PageSetup</TT> to
 927 include the option before each page and <TT>DocumentSetup</TT>
 928 to include the option once at the beginning of the document.</P>
 929
 930 <P>The sort order number is used to sort the printer commands
 931 associated with each option choice within the PostScript
 932 document. This allows you to setup certain options before others
 933 as required by the printer. For most CUPS raster printer
 934 drivers, the value <TT>10</TT> can be used for all options.</P>
 935
 936 <P>Once the option is specified, each option choice can be
 937 listed using the <TT>Choice</TT> directive:</P>
 938
 939 <pre class='example'>
 940 *<a href='ref-ppdcfile.html#Choice'>Choice</a> True/Yes "&lt;&lt;/cupsCompression 1&gt;&gt;setpagedevice"
 941 <a href='ref-ppdcfile.html#Choice'>Choice</a> False/No "&lt;&lt;/cupsCompression 0&gt;&gt;setpagedevice"
 942 </pre>
 943
 944 <P>The directive is followed by the choice name and optionally
 945 user text, and the PostScript commands that should be inserted
 946 when printing a file to this printer. The option name must
 947 conform to the PPD specification and cannot exceed 40 characters
 948 in length. If you specify user text, it cannot exceed 80
 949 characters in length.</P>
 950
 951 <P>The PostScript commands are also interpreted by any RIP
 952 filters, so these commands typically must be present for all
 953 option choices. Most commands take the form:</P>
 954
 955 <pre class='example'>
 956 &lt;&lt;/name value&gt;&gt;setpagedevice
 957 </pre>
 958
 959 <P>where <TT>name</TT> is the name of the PostScript page device
 960 attribute and <TT>value</TT> is the numeric or string value for
 961 that attribute.</P>
 962
 963
 964 <h3><a name='DEFINE'>Defining Constants</a></h3>
 965
 966 <P>Sometimes you will want to define constants for your drivers
 967 so that you can share values in different groups within the same
 968 driver information file, or to share values between different
 969 driver information files using the <TT>#include</TT> directive.
 970 The <TT>#define</TT> directive is used to define constants for
 971 use in your printer definitions:</P>
 972
 973 <pre class='example'>
 974 <a href='ref-ppdcfile.html#_define'>#define</a> NAME value
 975 </pre>
 976
 977 <P>The <TT>NAME</TT> is any sequence of letters, numbers, and
 978 the underscore. The <TT>value</TT> is a number or string; if the
 979 value contains spaces you must put double quotes around it, for
 980 example:</P>
 981
 982 <pre class='example'>
 983 <a href='ref-ppdcfile.html#_define'>#define</a> FOO "My String Value"
 984 </pre>
 985
 986 <P>Constants can also be defined on the command-line using the <tt>-D</tt>
 987 option:</P>
 988
 989 <pre class='command'>
 990 ppdc -DNAME="value" filename.drv
 991 </pre>
 992
 993 <P>Once defined, you use the notation <TT>$NAME</TT> to substitute the value of
 994 the constant in the file, for example:</P>
 995
 996 <pre class='example'>
 997 <a href='ref-ppdcfile.html#_define'>#define</a> MANUFACTURER "Foo"
 998 <a href='ref-ppdcfile.html#_define'>#define</a> FOO_600      0
 999 <a href='ref-ppdcfile.html#_define'>#define</a> FOO_1200     1
1000
1001 {
1002   <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "$MANUFACTURER"
1003   <a href='ref-ppdcfile.html#ModelNumber'>ModelNumber</a> $FOO_600
1004   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
1005   ...
1006 }
1007
1008 {
1009   <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "$MANUFACTURER"
1010   <a href='ref-ppdcfile.html#ModelNumber'>ModelNumber</a> $FOO_1200
1011   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2001"
1012   ...
1013 }
1014 </pre>
1015
1016 <P>Numeric constants can be bitwise OR'd together by placing the constants
1017 inside parenthesis, for example:</P>
1018
1019 <pre class='example'>
1020 <I>// ModelNumber capability bits</I>
1021 <a href='ref-ppdcfile.html#_define'>#define</a> DUPLEX 1
1022 <a href='ref-ppdcfile.html#_define'>#define</a> COLOR  2
1023
1024 ...
1025
1026 {
1027   <I>// Define a model number specifying the capabilities of the printer...</I>
1028   <a href='ref-ppdcfile.html#ModelNumber'>ModelNumber</a> ($DUPLEX $COLOR)
1029   ...
1030 }
1031 </pre>
1032
1033
1034 <h3><a name='CONDITIONAL'>Conditional Statements</a></h3>
1035
1036 <p>The PPD compiler supports conditional compilation using the <tt>#if</tt>,
1037 <tt>#elif</tt>, <tt>#else</tt>, and <tt>#endif</tt> directives. The <tt>#if</tt>
1038 and <tt>#elif</tt> directives are followed by a constant name or an expression.
1039 For example, to include a group of options when "ADVANCED" is defined:</p>
1040
1041 <pre class='example'>
1042 <a href='ref-ppdcfile.html#_if'>#if</a> ADVANCED
1043 <a href='ref-ppdcfile.html#Group'>Group</a> "Advanced/Advanced Options"
1044   <a href='ref-ppdcfile.html#Option'>Option</a> "fooCyanAdjust/Cyan Adjustment"
1045     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus10/+10%" ""
1046     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus5/+5%" ""
1047     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "none/No Adjustment" ""
1048     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus5/-5%" ""
1049     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus10/-10%" ""
1050   <a href='ref-ppdcfile.html#Option'>Option</a> "fooMagentaAdjust/Magenta Adjustment"
1051     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus10/+10%" ""
1052     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus5/+5%" ""
1053     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "none/No Adjustment" ""
1054     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus5/-5%" ""
1055     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus10/-10%" ""
1056   <a href='ref-ppdcfile.html#Option'>Option</a> "fooYellowAdjust/Yellow Adjustment"
1057     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus10/+10%" ""
1058     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus5/+5%" ""
1059     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "none/No Adjustment" ""
1060     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus5/-5%" ""
1061     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus10/-10%" ""
1062   <a href='ref-ppdcfile.html#Option'>Option</a> "fooBlackAdjust/Black Adjustment"
1063     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus10/+10%" ""
1064     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus5/+5%" ""
1065     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "none/No Adjustment" ""
1066     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus5/-5%" ""
1067     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus10/-10%" ""
1068 <a href='ref-ppdcfile.html#_endif'>#endif</a>
1069 </pre>
1070
1071
1072 <h3><a name='CONSTRAINTS'>Defining Constraints</a></h3>
1073
1074 <P>Constraints are strings that are used to specify that one or more option
1075 choices are incompatible, for example two-sided printing on transparency media.
1076 Constraints are also used to prevent the use of uninstalled features such as the
1077 duplexer unit, additional media trays, and so forth.</P>
1078
1079 <P>The <TT>UIConstraints</TT> directive is used to specify a constraint that is
1080 placed in the PPD file. The directive is followed by a string using one of the
1081 following formats:</P>
1082
1083 <pre class='example'>
1084 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Option1 *Option2"
1085 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Option1 Choice1 *Option2"
1086 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Option1 *Option2 Choice2"
1087 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Option1 Choice1 *Option2 Choice2"
1088 </pre>
1089
1090 <P>Each option name is preceded by the asterisk (<TT>*</TT>). If no choice is
1091 given for an option, then all choices <I>except</I> <TT>False</TT> and
1092 <TT>None</TT> will conflict with the other option and choice(s). Since the PPD
1093 compiler automatically adds reciprocal constraints (option A conflicts with
1094 option B, so therefore option B conflicts with option A), you need only specify
1095 the constraint once.</P>
1096
1097 <p class='example'><a name="LISTING5">Listing 5: "examples/constraint.drv"</a></p>
1098
1099 <pre class='example'>
1100
1101 <I>// Include standard font and media definitions</I>
1102 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
1103 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
1104
1105 <I>// List the fonts that are supported, in this case all standard fonts...</I>
1106 <a href='ref-ppdcfile.html#Font'>Font</a> *
1107
1108 <I>// Manufacturer, model name, and version</I>
1109 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
1110 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
1111 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
1112
1113 <I>// Each filter provided by the driver...</I>
1114 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
1115
1116 <I>// Supported page sizes</I>
1117 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
1118 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
1119
1120 <I>// Supported resolutions</I>
1121 *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
1122
1123 <I>// Installable Option Group</I>
1124 <a href='ref-ppdcfile.html#Group'>Group</a> "InstallableOptions/Options Installed"
1125
1126   <I>// Duplexing unit option</I>
1127   <a href='ref-ppdcfile.html#Option'>Option</a> "OptionDuplexer/Duplexing Unit" Boolean AnySetup 10
1128     <a href='ref-ppdcfile.html#Choice'>Choice</a> True/Installed ""
1129     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "False/Not Installed" ""
1130
1131 <I>// General Option Group</I>
1132 <a href='ref-ppdcfile.html#Group'>Group</a> General
1133
1134   <I>// Duplexing option</I>
1135   <a href='ref-ppdcfile.html#Option'>Option</a> "Duplex/Two-Sided Printing" PickOne AnySetup 10
1136     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "None/No" "&lt;&lt;/Duplex false&gt;&gt;setpagedevice""
1137     <a href='ref-ppdcfile.html#Choice'>Choice</a> "DuplexNoTumble/Long Edge Binding"
1138            "&lt;&lt;/Duplex true/Tumble false&gt;&gt;setpagedevice""
1139     <a href='ref-ppdcfile.html#Choice'>Choice</a> "DuplexTumble/Short Edge Binding"
1140            "&lt;&lt;/Duplex true/Tumble true&gt;&gt;setpagedevice""
1141
1142 <I>// Only allow duplexing if the duplexer is installed</I>
1143 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Duplex *OptionDuplexer False"
1144
1145 <I>// Specify the name of the PPD file we want to generate...</I>
1146 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
1147 </pre>
1148
1149 <P><A HREF="#LISTING5">Listing 5</A> shows a variation of the first example with
1150 an added <TT>Duplex</TT> option and installable option for the duplexer,
1151 <TT>OptionDuplex</TT>. A constraint is added at the end to specify that any
1152 choice of the <TT>Duplex</TT> option that is not <TT>None</TT> is incompatible
1153 with the "Duplexer Installed" option set to "Not Installed"
1154 (<TT>False</TT>):</P>
1155
1156 <pre class='example'>
1157 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Duplex *OptionDuplexer False"
1158 </pre>
1159
1160 <h4>Enhanced Constraints</h4>
1161
1162 <p>CUPS 1.4 supports constraints between 2 or more options using the
1163 <TT>Attribute</TT> directive. <TT>cupsUIConstraints</TT> attributes define
1164 the constraints, while <TT>cupsUIResolver</TT> attributes define option changes
1165 to resolve constraints. For example, we can specify the previous duplex
1166 constraint with a resolver that turns off duplexing with the following two
1167 lines:</p>
1168
1169 <pre class='example'>
1170 <a href='ref-ppdcfile.html#Attribute'>Attribute</a> cupsUIConstraints DuplexOff "*Duplex *OptionDuplexer False"
1171 <a href='ref-ppdcfile.html#Attribute'>Attribute</a> cupsUIResolver DuplexOff "*Duplex None"
1172 </pre>
1173 </div>
1174 </body>
1175 </html>