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 337 </head>
 338 <body>
 339 <div class='body'>
 340 <h1 class='title'>Introduction to the PPD Compiler</h1>
 341
 342 <P>This document describes how to use the CUPS PostScript Printer Description
 343 (PPD) file compiler. The PPD compiler generates PPD files from simple text files
 344 that describe the features and capabilities of one or more printers.</P>
 345
 346 <div class='summary'><table summary='General Information'>
 347 <tbody>
 348 <tr>
 349         <th>See Also</th>
 350         <td>Programming: <a href='raster-driver.html'>Developing Raster Printer Drivers</a><br>
 351         Programming: <a href='postscript-driver.html'>Developing PostScript Printer Drivers</a><br>
 352         Programming: <a href='api-filter.html'>Filter and Backend Programming</a><br>
 353         Programming: <a href='api-raster.html'>Raster API</a><br>
 354         References: <a href='ref-ppdcfile.html'>PPD Compiler Driver Information File Reference</a><br>
 355         Specifications: <a href='spec-ppd.html'>CUPS PPD Extensions</a></td>
 356 </tr>
 357 </tbody>
 358 </table></div>
 359 <h2 class="title">Contents</h2>
 360 <ul class="contents">
 361 <ul class="subcontents">
 362 <li><a href="#BASICS">The Basics</a></li>
 363 <li><a href="#DRV">Driver Information Files</a><ul class="subcontents">
 364 <li><a href="#SIMPLE">A Simple Example</a></li>
 365 <li><a href="#GROUPING">Grouping and Inheritance</a></li>
 366 <li><a href="#COLOR">Color Support</a></li>
 367 <li><a href="#OPTIONS">Defining Custom Options and Option Groups</a></li>
 368 <li><a href="#DEFINE">Defining Constants</a></li>
 369 <li><a href="#CONDITIONAL">Conditional Statements</a></li>
 370 <li><a href="#CONSTRAINTS">Defining Constraints</a></li>
 371 </ul></li>
 372 <h2 class='title'><a name='BASICS'>The Basics</a></h2>
 373
 374 <P>The PPD compiler, <a href='man-ppdc.html'><code>ppdc(1)</code></a>, is a
 375 simple command-line tool that takes a single <I>driver information file</I>,
 376 which by convention uses the extension <VAR>.drv</VAR>, and produces one or more
 377 PPD files that may be distributed with your printer drivers for use with CUPS.
 378 For example, you would run the following command to create the English language
 379 PPD files defined by the driver information file <VAR>mydrivers.drv</VAR>:</P>
 380
 381 <pre class='command'>
 382 ppdc mydrivers.drv
 383 </pre>
 384
 385 <P>The PPD files are placed in a subdirectory called
 386 <VAR>ppd</VAR>. The <TT>-d</TT> option is used to put the PPD
 387 files in a different location, for example:</p>
 388
 389 <pre class='command'>
 390 ppdc -d myppds mydrivers.drv
 391 </pre>
 392
 393 <P>places the PPD files in a subdirectory named
 394 <VAR>myppds</VAR>. Finally, use the <TT>-l</TT> option to
 395 specify the language localization for the PPD files that are
 396 created, for example:</P>
 397
 398 <pre class='command'>
 399 ppdc -d myppds/de -l de mydrivers.drv
 400 ppdc -d myppds/en -l en mydrivers.drv
 401 ppdc -d myppds/es -l es mydrivers.drv
 402 ppdc -d myppds/fr -l fr mydrivers.drv
 403 ppdc -d myppds/it -l it mydrivers.drv
 404 </pre>
 405
 406 <P>creates PPD files in German (de), English (en), Spanish (es),
 407 French (fr), and Italian (it) in the corresponding
 408 subdirectories. Specify multiple languages (separated by commas) to produce
 409 "globalized" PPD files:</p>
 410
 411 <pre class='command'>
 412 ppdc -d myppds -l de,en,es,fr,it mydrivers.drv
 413 </pre>
 414
 415
 416 <h2 class='title'><a name='DRV'>Driver Information Files</a></h2>
 417
 418 <P>The driver information files accepted by the PPD compiler are
 419 plain text files that define the various attributes and options
 420 that are included in the PPD files that are generated. A driver
 421 information file can define the information for one or more printers and
 422 their corresponding PPD files.</P>
 423
 424 <p class='example'><a name="LISTING1">Listing 1: "examples/minimum.drv"</a></p>
 425
 426 <pre class='example'>
 427 <I>// Include standard font and media definitions</I>
 428 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 429 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 430
 431 <I>// List the fonts that are supported, in this case all standard fonts...</I>
 432 <a href='ref-ppdcfile.html#Font'>Font</a> *
 433
 434 <I>// Manufacturer, model name, and version</I>
 435 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 436 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 437 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 438
 439 <I>// Each filter provided by the driver...</I>
 440 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 441
 442 <I>// Supported page sizes</I>
 443 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 444 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 445
 446 <I>// Supported resolutions</I>
 447 *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 448
 449 <I>// Specify the name of the PPD file we want to generate...</I>
 450 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 451 </pre>
 452
 453
 454 <h3><a name='SIMPLE'>A Simple Example</a></h3>
 455
 456 <P>The example in <A HREF="#LISTING1">Listing 1</A> shows a driver information
 457 file which defines the minimum required attributes to provide a valid PPD file.
 458 The first part of the file includes standard definition files for fonts and
 459 media sizes:</P>
 460
 461 <pre class='example'>
 462 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 463 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 464 </pre>
 465
 466 <P>The <TT>#include</TT> directive works just like the C/C++ include directive;
 467 files included using the angle brackets (<TT>&lt;filename&gt;</TT>) are found
 468 in any of the standard include directories and files included using quotes
 469 (<TT>"filename"</TT>) are found in the same directory as the source or include
 470 file. The <TT>&lt;font.defs&gt;</TT> include file defines the standard fonts
 471 which are included with GPL Ghostscript and the Apple PDF RIP, while the
 472 <TT>&lt;media.defs&gt;</TT> include file defines the standard media sizes
 473 listed in Appendix B of the Adobe PostScript Printer Description File Format
 474 Specification.</P>
 475
 476 <P>CUPS provides several other standard include files:</P>
 477
 478 <UL>
 479
 480         <LI><TT>&lt;epson.h&gt;</TT> - Defines all of the rastertoepson driver
 481         constants.</LI>
 482
 483         <LI><TT>&lt;escp.h&gt;</TT> - Defines all of the rastertoescpx driver
 484         constants.</LI>
 485
 486         <LI><TT>&lt;hp.h&gt;</TT> - Defines all of the rastertohp driver
 487         constants.</LI>
 488
 489         <LI><TT>&lt;label.h&gt;</TT> - Defines all of the rastertolabel driver
 490         constants.</LI>
 491
 492         <LI><TT>&lt;pcl.h&gt;</TT> - Defines all of the rastertopclx driver
 493         constants.</LI>
 494
 495         <LI><TT>&lt;raster.defs&gt;</TT> - Defines all of the CUPS raster format
 496         constants.</LI>
 497
 498 </UL>
 499
 500 <P>Next we list all of the fonts that are available in the driver; for CUPS
 501 raster drivers, the following line is all that is usually supplied:</P>
 502
 503 <pre class='example'>
 504 <a href='ref-ppdcfile.html#Font'>Font</a> *
 505 </pre>
 506
 507 <P>The <TT>Font</TT> directive specifies the name of a single font or the
 508 asterisk to specify all fonts. For example, you would use the following line to
 509 define an additional bar code font that you are supplying with your printer
 510 driver:</P>
 511
 512 <pre class='example'>
 513 <I>//   name         encoding  version  charset  status</I>
 514 <a href='ref-ppdcfile.html#Font'>Font</a> Barcode-Foo  Special   "(1.0)"  Special  ROM
 515 </pre>
 516
 517 <P>The name of the font is <TT>Barcode-Foo</TT>. Since it is not a standard
 518 text font, the encoding and charset name <TT>Special</TT> is used. The version
 519 number is <TT>1.0</TT> and the status (where the font is located) is
 520 <TT>ROM</TT> to indicate that the font does not need to be embedded in
 521 documents that use the font for this printer.</P>
 522
 523 <P>Third comes the manufacturer, model name, and version number information
 524 strings:</P>
 525
 526 <pre class='example'>
 527 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 528 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 529 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 530 </pre>
 531
 532 <P>These strings are used when the user (or auto-configuration program) selects
 533 the printer driver for a newly connected device.</p>
 534
 535 <P>The list of filters comes after the information strings; for the example in
 536 <A HREF="#LISTING1">Listing 1</A>, we have a single filter that takes CUPS
 537 raster data:</P>
 538
 539 <pre class='example'>
 540 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 541 </pre>
 542
 543 <P>Each filter specified in the driver information file is the equivalent of a
 544 printer driver for that format; if a user submits a print job in a different
 545 format, CUPS figures out the sequence of commands that will produce a supported
 546 format for the least relative cost.</P>
 547
 548 <P>Once we have defined the driver information we specify the supported options.
 549 For the example driver we support a single resolution of 600 dots per inch and
 550 two media sizes, A4 and Letter:</P>
 551
 552 <pre class='example'>
 553 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 554 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 555
 556 *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 557 </pre>
 558
 559 <P>The asterisk in front of the <TT>MediaSize</TT> and <TT>Resolution</TT>
 560 directives specify that those option choices are the default. The
 561 <TT>MediaSize</TT> directive is followed by a media size name which is normally
 562 defined in the <TT>&lt;media.defs&gt;</TT> file and corresponds to a standard
 563 Adobe media size name. If the default media size is <TT>Letter</TT>, the PPD
 564 compiler will override it to be <TT>A4</TT> for non-English localizations for
 565 you automatically.</P>
 566
 567 <P>The <TT>Resolution</TT> directive accepts several values after it as
 568 follows:</P>
 569
 570 <OL>
 571
 572         <LI>Colorspace for this resolution, if any. In the example file, the
 573         colorspace <TT>k</TT> is used which corresponds to black. For printer
 574         drivers that support color printing, this field is usually specified as
 575         "-" for "no change".</LI>
 576
 577         <LI>Bits per color. In the example file, we define 8 bits per color, for
 578         a continuous-tone grayscale output. All versions of CUPS support 1 and
 579         8 bits per color.  CUPS 1.2 and higher (Mac OS X 10.5 and higher) also
 580         supports 16 bits per color.</LI>
 581
 582         <LI>Rows per band. In the example file, we define 0 rows per band to
 583         indicate that our printer driver does not process the page in
 584         bands.</LI>
 585
 586         <LI>Row feed. In the example, we define the feed value to be 0 to
 587         indicate that our printer driver does not interleave the output.</LI>
 588
 589         <LI>Row step. In the example, we define the step value to be 0 to
 590         indicate that our printer driver does not interleave the output. This
 591         value normally indicates the spacing between the nozzles of an inkjet
 592         printer - when combined with the previous two values, it informs the
 593         driver how to stagger the output on the page to produce interleaved
 594         lines on the page for higher-resolution output.</LI>
 595
 596         <LI>Choice name and text. In the example, we define the choice name and
 597         text to be <TT>"600dpi/600 DPI"</TT>. The name and text are separated by
 598         slash (<TT>/</TT>) character; if no text is specified, then the name is
 599         used as the text. The PPD compiler parses the name to determine the
 600         actual resolution; the name can be of the form
 601         <TT><I>RESOLUTION</I>dpi</TT> for resolutions that are equal
 602         horizontally and vertically or <TT><I>HRES</I>x<I>VRES</I>dpi</TT> for
 603         isometric resolutions. Only integer resolution values are supported, so
 604         a resolution name of <TT>300dpi</TT> is valid while <TT>300.1dpi</TT> is
 605         not.</LI>
 606
 607 </OL>
 608
 609 <P>Finally, the <TT>PCFileName</TT> directive specifies that the named PPD file
 610 should be written for the current driver definitions:</P>
 611
 612 <pre class='example'>
 613 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 614 </pre>
 615
 616 <P>The filename follows the directive and <I>must</I> conform to the Adobe
 617 filename requirements in the Adobe Postscript Printer Description File Format
 618 Specification. Specifically, the filename may not exceed 8 characters followed
 619 by the extension <VAR>.ppd</VAR>. The <TT>FileName</TT> directive can be used to
 620 specify longer filenames:</P>
 621
 622 <pre class='example'>
 623 <a href='ref-ppdcfile.html#FileName'>FileName</a> "FooJet 2000"
 624 </pre>
 625
 626
 627 <h3><a name='GROUPING'>Grouping and Inheritance</a></h3>
 628
 629 <P>The previous example created a single PPD file. Driver information files can
 630 also define multiple printers by using the PPD compiler grouping functionality.
 631 Directives are grouped using the curly braces (<TT>{</TT> and <TT>}</TT>) and
 632 every group that uses the <TT>PCFileName</TT> or <TT>FileName</TT> directives
 633 produces a PPD file with that name. <A HREF="#LISTING2">Listing 2</A> shows a
 634 variation of the original example that uses two groups to define two printers
 635 that share the same printer driver filter but provide two different resolution
 636 options.</P>
 637
 638 <p class='example'><a name="LISTING2">Listing 2: "examples/grouping.drv"</a></p>
 639
 640 <pre class='example'>
 641
 642 <I>// Include standard font and media definitions</I>
 643 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 644 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 645
 646 <I>// List the fonts that are supported, in this case all standard fonts...</I>
 647 <a href='ref-ppdcfile.html#Font'>Font</a> *
 648
 649 <I>// Manufacturer and version</I>
 650 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 651 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 652
 653 <I>// Each filter provided by the driver...</I>
 654 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 655
 656 <I>// Supported page sizes</I>
 657 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 658 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 659
 660 {
 661   <I>// Supported resolutions</I>
 662   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 663
 664   <I>// Specify the model name and filename...</I>
 665   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 666   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 667 }
 668
 669 {
 670   <I>// Supported resolutions</I>
 671   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "1200dpi/1200 DPI"
 672
 673   <I>// Specify the model name and filename...</I>
 674   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2001"
 675   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojt2k1.ppd"
 676 }
 677 </pre>
 678
 679 <P>The second example is essentially the same as the first, except that each
 680 printer model is defined inside of a pair of curly braces. For example, the
 681 first printer is defined using:</P>
 682
 683 <pre class='example'>
 684 {
 685   // Supported resolutions
 686   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 687
 688   // Specify the model name and filename...
 689   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 690   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 691 }
 692 </pre>
 693
 694 <P>The printer <I>inherits</I> all of the definitions from the parent group (the
 695 top part of the file) and adds the additional definitions inside the curly
 696 braces for that printer driver. When we define the second group, it also
 697 inherits the same definitions from the parent group but <I>none</I> of the
 698 definitions from the first driver. Groups can be nested to any number of levels
 699 to support variations of similar models without duplication of information.</P>
 700
 701
 702 <h3><a name='COLOR'>Color Support</a></h3>
 703
 704 <P>For printer drivers that support color printing, the
 705 <TT>ColorDevice</TT> and <TT>ColorModel</TT> directives should be
 706 used to tell the printing system that color output is desired
 707 and in what formats. <A HREF="#LISTING3">Listing 3</A> shows a
 708 variation of the previous example which includes a color printer
 709 that supports printing at 300 and 600 DPI.</P>
 710
 711 <P>The key changes are the addition of the <TT>ColorDevice</TT>
 712 directive:</P>
 713
 714 <pre class='example'>
 715 <a href='ref-ppdcfile.html#ColorDevice'>ColorDevice</a> true
 716 </pre>
 717
 718 <P>which tells the printing system that the printer supports
 719 color printing, and the <TT>ColorModel</TT> directives:</P>
 720
 721 <pre class='example'>
 722 <a href='ref-ppdcfile.html#ColorModel'>ColorModel</a> Gray/Grayscale w chunky 0
 723 *<a href='ref-ppdcfile.html#ColorModel'>ColorModel</a> RGB/Color rgb chunky 0
 724 </pre>
 725
 726 <P>which tell the printing system which colorspaces are supported by the printer
 727 driver for color printing. Each of the <TT>ColorModel</TT> directives is
 728 followed by the option name and text (<TT>Gray/Grayscale</TT> and
 729 <TT>RGB/Color</TT>), the colorspace name (<TT>w</TT> and <TT>rgb</TT>), the
 730 color organization (<TT>chunky</TT>), and the compression mode number
 731 (<TT>0</TT>) to be passed to the driver. The option name can be any of the
 732 standard Adobe <TT>ColorModel</TT> names:</P>
 733
 734 <UL>
 735
 736         <LI><TT>Gray</TT> - Grayscale output.
 737
 738         <LI><TT>RGB</TT> - Color output, typically using the RGB
 739         colorspace, but without a separate black channel.
 740
 741         <LI><TT>CMYK</TT> - Color output with a separate black
 742         channel.
 743
 744 </UL>
 745
 746 <P>Custom names can be used, however it is recommended that you use your vendor
 747 prefix for any custom names, for example "fooName".</P>
 748
 749 <P>The colorspace name can be any of the following universally supported
 750 colorspaces:</P>
 751
 752 <UL>
 753         <LI><TT>w</TT> - Luminance</LI>
 754
 755         <LI><TT>rgb</TT> - Red, green, blue</LI>
 756
 757         <LI><TT>k</TT> - Black</LI>
 758
 759         <LI><TT>cmy</TT> - Cyan, magenta, yellow</LI>
 760
 761         <LI><TT>cmyk</TT> - Cyan, magenta, yellow, black</LI>
 762
 763 </UL>
 764
 765 <P>The color organization can be any of the following values:</P>
 766
 767 <UL>
 768
 769         <LI><TT>chunky</TT> - Color values are passed together on a line
 770         as RGB RGB RGB RGB</LI>
 771
 772         <LI><TT>banded</TT> - Color values are passed separately
 773         on a line as RRRR GGGG BBBB; not supported by the Apple
 774         RIP filters</LI>
 775
 776         <LI><TT>planar</TT> - Color values are passed separately
 777         on a page as RRRR RRRR RRRR ... GGGG GGGG GGGG ... BBBB
 778         BBBB BBBB; not supported by the Apple RIP filters</LI>
 779
 780 </UL>
 781
 782 <P>The compression mode value is passed to the driver in the
 783 <TT>cupsCompression</TT> attribute. It is traditionally used to select an
 784 appropriate compression mode for the color model but can be used for any
 785 purpose, such as specifying a photo mode vs. standard mode.</P>
 786
 787 <p class='example'><a name="LISTING3">Listing 3: "examples/color.drv"</a></p>
 788
 789 <pre class='example'>
 790
 791 <I>// Include standard font and media definitions</I>
 792 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 793 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 794
 795 <I>// List the fonts that are supported, in this case all standard fonts...</I>
 796 <a href='ref-ppdcfile.html#Font'>Font</a> *
 797
 798 <I>// Manufacturer and version</I>
 799 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 800 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 801
 802 <I>// Each filter provided by the driver...</I>
 803 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 804
 805 <I>// Supported page sizes</I>
 806 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 807 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 808
 809 {
 810   <I>// Supported resolutions</I>
 811   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 812
 813   <I>// Specify the model name and filename...</I>
 814   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 815   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 816 }
 817
 818 {
 819   <I>// Supports color printing</I>
 820   <a href='ref-ppdcfile.html#ColorDevice'>ColorDevice</a> true
 821
 822   <I>// Supported colorspaces</I>
 823   <a href='ref-ppdcfile.html#ColorModel'>ColorModel</a> Gray/Grayscale w chunky 0
 824   *<a href='ref-ppdcfile.html#ColorModel'>ColorModel</a> RGB/Color rgb chunky 0
 825
 826   <I>// Supported resolutions</I>
 827   *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> - 8 0 0 0 "300dpi/300 DPI"
 828   <a href='ref-ppdcfile.html#Resolution'>Resolution</a> - 8 0 0 0 "600dpi/600 DPI"
 829
 830   <I>// Specify the model name and filename...</I>
 831   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet Color"
 832   <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojetco.ppd"
 833 }
 834 </pre>
 835
 836
 837 <h3><a name='OPTIONS'>Defining Custom Options and Option Groups</a></h3>
 838
 839 <P>The <TT>Group</TT>, <TT>Option</TT>, and <TT>Choice</TT>
 840 directives are used to define or select a group, option, or
 841 choice. <A HREF="#LISTING4">Listing 4</A> shows a variation of
 842 the first example that provides two custom options in a group
 843 named "Footasm".</P>
 844
 845 <p class='example'><a name="LISTING4">Listing 4: "examples/custom.drv"</a></p>
 846
 847 <pre class='example'>
 848
 849 <I>// Include standard font and media definitions</I>
 850 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
 851 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
 852
 853 <I>// List the fonts that are supported, in this case all standard fonts...</I>
 854 <a href='ref-ppdcfile.html#Font'>Font</a> *
 855
 856 <I>// Manufacturer, model name, and version</I>
 857 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
 858 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
 859 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
 860
 861 <I>// Each filter provided by the driver...</I>
 862 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
 863
 864 <I>// Supported page sizes</I>
 865 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
 866 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
 867
 868 <I>// Supported resolutions</I>
 869 *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
 870
 871 <I>// Option Group</I>
 872 <a href='ref-ppdcfile.html#Group'>Group</a> "Footasm"
 873
 874   <I>// Boolean option</I>
 875   <a href='ref-ppdcfile.html#Option'>Option</a> "fooEnhance/Resolution Enhancement" Boolean AnySetup 10
 876     *<a href='ref-ppdcfile.html#Choice'>Choice</a> True/Yes "&lt;&lt;/cupsCompression 1&gt;&gt;setpagedevice"
 877     <a href='ref-ppdcfile.html#Choice'>Choice</a> False/No "&lt;&lt;/cupsCompression 0&gt;&gt;setpagedevice"
 878
 879   <I>// Multiple choice option</I>
 880   <a href='ref-ppdcfile.html#Option'>Option</a> "fooOutputType/Output Quality" PickOne AnySetup 10
 881     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "Auto/Automatic Selection"
 882             "&lt;&lt;/OutputType(Auto)&gt;&gt;setpagedevice""
 883     <a href='ref-ppdcfile.html#Choice'>Choice</a> "Text/Optimize for Text"
 884             "&lt;&lt;/OutputType(Text)&gt;&gt;setpagedevice""
 885     <a href='ref-ppdcfile.html#Choice'>Choice</a> "Graph/Optimize for Graphics"
 886             "&lt;&lt;/OutputType(Graph)&gt;&gt;setpagedevice""
 887     <a href='ref-ppdcfile.html#Choice'>Choice</a> "Photo/Optimize for Photos"
 888             "&lt;&lt;/OutputType(Photo)&gt;&gt;setpagedevice""
 889
 890 <I>// Specify the name of the PPD file we want to generate...</I>
 891 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
 892 </pre>
 893
 894 <P>The custom group is introduced by the <TT>Group</TT>
 895 directive which is followed by the name and optionally text for
 896 the user:</P>
 897
 898 <pre class='example'>
 899 <a href='ref-ppdcfile.html#Group'>Group</a> "Footasm/Footastic Options"
 900 </pre>
 901
 902 <P>The group name must conform to the PPD specification and
 903 cannot exceed 40 characters in length. If you specify user text,
 904 it cannot exceed 80 characters in length. The groups
 905 <TT>General</TT>, <TT>Extra</TT>, and
 906 <TT>InstallableOptions</TT> are predefined by CUPS; the general
 907 and extra groups are filled by the UI options defined by the PPD
 908 specification. The <TT>InstallableOptions</TT> group is reserved
 909 for options that define whether accessories for the printer
 910 (duplexer unit, finisher, stapler, etc.) are installed.</P>
 911
 912 <P>Once the group is specified, the <TT>Option</TT> directive is
 913 used to introduce a new option:</P>
 914
 915 <pre class='example'>
 916 <a href='ref-ppdcfile.html#Option'>Option</a> "fooEnhance/Resolution Enhancement" Boolean AnySetup 10
 917 </pre>
 918
 919 <P>The directive is followed by the name of the option and any
 920 optional user text, the option type, the PostScript document group, and
 921 the sort order number. The option name must conform to the PPD specification
 922 and cannot exceed 40 characters in length. If you specify user text, it
 923 cannot exceed 80 characters in length.</P>
 924
 925 <P>The option type can be <TT>Boolean</TT> for true/false
 926 selections, <TT>PickOne</TT> for picking one of many choices, or
 927 <TT>PickMany</TT> for picking zero or more choices. Boolean
 928 options can have at most two choices with the names
 929 <TT>False</TT> and <TT>True</TT>. Pick options can have any
 930 number of choices, although for Windows compatibility reasons
 931 the number of choices should not exceed 255.</P>
 932
 933 <P>The PostScript document group is typically <TT>AnySetup</TT>,
 934 meaning that the option can be introduced at any point in the
 935 PostScript document. Other values include <TT>PageSetup</TT> to
 936 include the option before each page and <TT>DocumentSetup</TT>
 937 to include the option once at the beginning of the document.</P>
 938
 939 <P>The sort order number is used to sort the printer commands
 940 associated with each option choice within the PostScript
 941 document. This allows you to setup certain options before others
 942 as required by the printer. For most CUPS raster printer
 943 drivers, the value <TT>10</TT> can be used for all options.</P>
 944
 945 <P>Once the option is specified, each option choice can be
 946 listed using the <TT>Choice</TT> directive:</P>
 947
 948 <pre class='example'>
 949 *<a href='ref-ppdcfile.html#Choice'>Choice</a> True/Yes "&lt;&lt;/cupsCompression 1&gt;&gt;setpagedevice"
 950 <a href='ref-ppdcfile.html#Choice'>Choice</a> False/No "&lt;&lt;/cupsCompression 0&gt;&gt;setpagedevice"
 951 </pre>
 952
 953 <P>The directive is followed by the choice name and optionally
 954 user text, and the PostScript commands that should be inserted
 955 when printing a file to this printer. The option name must
 956 conform to the PPD specification and cannot exceed 40 characters
 957 in length. If you specify user text, it cannot exceed 80
 958 characters in length.</P>
 959
 960 <P>The PostScript commands are also interpreted by any RIP
 961 filters, so these commands typically must be present for all
 962 option choices. Most commands take the form:</P>
 963
 964 <pre class='example'>
 965 &lt;&lt;/name value&gt;&gt;setpagedevice
 966 </pre>
 967
 968 <P>where <TT>name</TT> is the name of the PostScript page device
 969 attribute and <TT>value</TT> is the numeric or string value for
 970 that attribute.</P>
 971
 972
 973 <h3><a name='DEFINE'>Defining Constants</a></h3>
 974
 975 <P>Sometimes you will want to define constants for your drivers
 976 so that you can share values in different groups within the same
 977 driver information file, or to share values between different
 978 driver information files using the <TT>#include</TT> directive.
 979 The <TT>#define</TT> directive is used to define constants for
 980 use in your printer definitions:</P>
 981
 982 <pre class='example'>
 983 <a href='ref-ppdcfile.html#_define'>#define</a> NAME value
 984 </pre>
 985
 986 <P>The <TT>NAME</TT> is any sequence of letters, numbers, and
 987 the underscore. The <TT>value</TT> is a number or string; if the
 988 value contains spaces you must put double quotes around it, for
 989 example:</P>
 990
 991 <pre class='example'>
 992 <a href='ref-ppdcfile.html#_define'>#define</a> FOO "My String Value"
 993 </pre>
 994
 995 <P>Constants can also be defined on the command-line using the <tt>-D</tt>
 996 option:</P>
 997
 998 <pre class='command'>
 999 ppdc -DNAME="value" filename.drv
1000 </pre>
1001
1002 <P>Once defined, you use the notation <TT>$NAME</TT> to substitute the value of
1003 the constant in the file, for example:</P>
1004
1005 <pre class='example'>
1006 <a href='ref-ppdcfile.html#_define'>#define</a> MANUFACTURER "Foo"
1007 <a href='ref-ppdcfile.html#_define'>#define</a> FOO_600      0
1008 <a href='ref-ppdcfile.html#_define'>#define</a> FOO_1200     1
1009
1010 {
1011   <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "$MANUFACTURER"
1012   <a href='ref-ppdcfile.html#ModelNumber'>ModelNumber</a> $FOO_600
1013   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
1014   ...
1015 }
1016
1017 {
1018   <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "$MANUFACTURER"
1019   <a href='ref-ppdcfile.html#ModelNumber'>ModelNumber</a> $FOO_1200
1020   <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2001"
1021   ...
1022 }
1023 </pre>
1024
1025 <P>Numeric constants can be bitwise OR'd together by placing the constants
1026 inside parenthesis, for example:</P>
1027
1028 <pre class='example'>
1029 <I>// ModelNumber capability bits</I>
1030 <a href='ref-ppdcfile.html#_define'>#define</a> DUPLEX 1
1031 <a href='ref-ppdcfile.html#_define'>#define</a> COLOR  2
1032
1033 ...
1034
1035 {
1036   <I>// Define a model number specifying the capabilities of the printer...</I>
1037   <a href='ref-ppdcfile.html#ModelNumber'>ModelNumber</a> ($DUPLEX $COLOR)
1038   ...
1039 }
1040 </pre>
1041
1042
1043 <h3><a name='CONDITIONAL'>Conditional Statements</a></h3>
1044
1045 <p>The PPD compiler supports conditional compilation using the <tt>#if</tt>,
1046 <tt>#elif</tt>, <tt>#else</tt>, and <tt>#endif</tt> directives. The <tt>#if</tt>
1047 and <tt>#elif</tt> directives are followed by a constant name or an expression.
1048 For example, to include a group of options when "ADVANCED" is defined:</p>
1049
1050 <pre class='example'>
1051 <a href='ref-ppdcfile.html#_if'>#if</a> ADVANCED
1052 <a href='ref-ppdcfile.html#Group'>Group</a> "Advanced/Advanced Options"
1053   <a href='ref-ppdcfile.html#Option'>Option</a> "fooCyanAdjust/Cyan Adjustment"
1054     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus10/+10%" ""
1055     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus5/+5%" ""
1056     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "none/No Adjustment" ""
1057     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus5/-5%" ""
1058     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus10/-10%" ""
1059   <a href='ref-ppdcfile.html#Option'>Option</a> "fooMagentaAdjust/Magenta Adjustment"
1060     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus10/+10%" ""
1061     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus5/+5%" ""
1062     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "none/No Adjustment" ""
1063     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus5/-5%" ""
1064     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus10/-10%" ""
1065   <a href='ref-ppdcfile.html#Option'>Option</a> "fooYellowAdjust/Yellow Adjustment"
1066     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus10/+10%" ""
1067     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus5/+5%" ""
1068     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "none/No Adjustment" ""
1069     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus5/-5%" ""
1070     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus10/-10%" ""
1071   <a href='ref-ppdcfile.html#Option'>Option</a> "fooBlackAdjust/Black Adjustment"
1072     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus10/+10%" ""
1073     <a href='ref-ppdcfile.html#Choice'>Choice</a> "plus5/+5%" ""
1074     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "none/No Adjustment" ""
1075     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus5/-5%" ""
1076     <a href='ref-ppdcfile.html#Choice'>Choice</a> "minus10/-10%" ""
1077 <a href='ref-ppdcfile.html#_endif'>#endif</a>
1078 </pre>
1079
1080
1081 <h3><a name='CONSTRAINTS'>Defining Constraints</a></h3>
1082
1083 <P>Constraints are strings that are used to specify that one or more option
1084 choices are incompatible, for example two-sided printing on transparency media.
1085 Constraints are also used to prevent the use of uninstalled features such as the
1086 duplexer unit, additional media trays, and so forth.</P>
1087
1088 <P>The <TT>UIConstraints</TT> directive is used to specify a constraint that is
1089 placed in the PPD file. The directive is followed by a string using one of the
1090 following formats:</P>
1091
1092 <pre class='example'>
1093 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Option1 *Option2"
1094 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Option1 Choice1 *Option2"
1095 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Option1 *Option2 Choice2"
1096 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Option1 Choice1 *Option2 Choice2"
1097 </pre>
1098
1099 <P>Each option name is preceded by the asterisk (<TT>*</TT>). If no choice is
1100 given for an option, then all choices <I>except</I> <TT>False</TT> and
1101 <TT>None</TT> will conflict with the other option and choice(s). Since the PPD
1102 compiler automatically adds reciprocal constraints (option A conflicts with
1103 option B, so therefore option B conflicts with option A), you need only specify
1104 the constraint once.</P>
1105
1106 <p class='example'><a name="LISTING5">Listing 5: "examples/constraint.drv"</a></p>
1107
1108 <pre class='example'>
1109
1110 <I>// Include standard font and media definitions</I>
1111 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;font.defs&gt;
1112 <a href='ref-ppdcfile.html#_include'>#include</a> &lt;media.defs&gt;
1113
1114 <I>// List the fonts that are supported, in this case all standard fonts...</I>
1115 <a href='ref-ppdcfile.html#Font'>Font</a> *
1116
1117 <I>// Manufacturer, model name, and version</I>
1118 <a href='ref-ppdcfile.html#Manufacturer'>Manufacturer</a> "Foo"
1119 <a href='ref-ppdcfile.html#ModelName'>ModelName</a> "FooJet 2000"
1120 <a href='ref-ppdcfile.html#Version'>Version</a> 1.0
1121
1122 <I>// Each filter provided by the driver...</I>
1123 <a href='ref-ppdcfile.html#Filter'>Filter</a> application/vnd.cups-raster 100 rastertofoo
1124
1125 <I>// Supported page sizes</I>
1126 *<a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> Letter
1127 <a href='ref-ppdcfile.html#MediaSize'>MediaSize</a> A4
1128
1129 <I>// Supported resolutions</I>
1130 *<a href='ref-ppdcfile.html#Resolution'>Resolution</a> k 8 0 0 0 "600dpi/600 DPI"
1131
1132 <I>// Installable Option Group</I>
1133 <a href='ref-ppdcfile.html#Group'>Group</a> "InstallableOptions/Options Installed"
1134
1135   <I>// Duplexing unit option</I>
1136   <a href='ref-ppdcfile.html#Option'>Option</a> "OptionDuplexer/Duplexing Unit" Boolean AnySetup 10
1137     <a href='ref-ppdcfile.html#Choice'>Choice</a> True/Installed ""
1138     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "False/Not Installed" ""
1139
1140 <I>// General Option Group</I>
1141 <a href='ref-ppdcfile.html#Group'>Group</a> General
1142
1143   <I>// Duplexing option</I>
1144   <a href='ref-ppdcfile.html#Option'>Option</a> "Duplex/Two-Sided Printing" PickOne AnySetup 10
1145     *<a href='ref-ppdcfile.html#Choice'>Choice</a> "None/No" "&lt;&lt;/Duplex false&gt;&gt;setpagedevice""
1146     <a href='ref-ppdcfile.html#Choice'>Choice</a> "DuplexNoTumble/Long Edge Binding"
1147            "&lt;&lt;/Duplex true/Tumble false&gt;&gt;setpagedevice""
1148     <a href='ref-ppdcfile.html#Choice'>Choice</a> "DuplexTumble/Short Edge Binding"
1149            "&lt;&lt;/Duplex true/Tumble true&gt;&gt;setpagedevice""
1150
1151 <I>// Only allow duplexing if the duplexer is installed</I>
1152 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Duplex *OptionDuplexer False"
1153
1154 <I>// Specify the name of the PPD file we want to generate...</I>
1155 <a href='ref-ppdcfile.html#PCFileName'>PCFileName</a> "foojet2k.ppd"
1156 </pre>
1157
1158 <P><A HREF="#LISTING5">Listing 5</A> shows a variation of the first example with
1159 an added <TT>Duplex</TT> option and installable option for the duplexer,
1160 <TT>OptionDuplex</TT>. A constraint is added at the end to specify that any
1161 choice of the <TT>Duplex</TT> option that is not <TT>None</TT> is incompatible
1162 with the "Duplexer Installed" option set to "Not Installed"
1163 (<TT>False</TT>):</P>
1164
1165 <pre class='example'>
1166 <a href='ref-ppdcfile.html#UIConstraints'>UIConstraints</a> "*Duplex *OptionDuplexer False"
1167 </pre>
1168
1169 <h4>Enhanced Constraints</h4>
1170
1171 <p>CUPS 1.4 supports constraints between 2 or more options using the
1172 <TT>Attribute</TT> directive. <TT>cupsUIConstraints</TT> attributes define
1173 the constraints, while <TT>cupsUIResolver</TT> attributes define option changes
1174 to resolve constraints. For example, we can specify the previous duplex
1175 constraint with a resolver that turns off duplexing with the following two
1176 lines:</p>
1177
1178 <pre class='example'>
1179 <a href='ref-ppdcfile.html#Attribute'>Attribute</a> cupsUIConstraints DuplexOff "*Duplex *OptionDuplexer False"
1180 <a href='ref-ppdcfile.html#Attribute'>Attribute</a> cupsUIResolver DuplexOff "*Duplex None"
1181 </pre>
1182 </div>
1183 </body>
1184 </html>