This file describes issues that packagers and distributors of
Gutenprint should be aware of.  This information is targeted at Linux
distributions and others who deliver Gutenprint packages intended for
end-user use.

1) As of 5.2 and until further notice, Gutenprint will no longer
   deliver separate "development" and "stable" release series.

   The point release will be advanced between beta/RC releases and
   stable releases.  The first stable release of 5.2 will be numbered
   5.2.1; the betas and release candidates will be numbered
   5.2.0-betaN or 5.2.0-rcN.  Any betas for the next stable release
   will be numbered 5.2.2-betaN; the next stable release will be
   numbered 5.2.3 (if there are beta or release candidate builds) or
   5.2.2 (if there are not).

   This ensures that the highest numbered release is always the most
   current, and that there will be no confusion between beta releases
   and stable releases.  Our experience with 5.0 was that many users
   continued to use beta releases of 5.0 even after 5.0.0 was
   released, and worse, in some cases referred to the 5.0.0-beta2
   release (for example) as "5.0.2".  We believe that the numbering
   scheme described above will avoid that problem.

2) We request that you subscribe to
   gimp-print-devel@lists.sourceforge.net to get the latest
   information about upcoming changes.

3) If you intend to make any changes or patches to the source code of
   this package, we request that you inform us of these changes and
   discuss them with us prior to distribution, and identify a point of
   contact to us.

   While this is not required by the GPL, we would greatly appreciate
   knowing about any changes you plan to make for three reasons:

   * The changes may benefit all users of Gutenprint.

   * We may have already considered this kind of change in the past
     and elected not to make it, or may be planning to make this kind
     of change in a different way from what you have done.
     Coordination in this case may save everyone a lot of work.

   * If we receive bug reports or support requests from users of your
     package, we will either know who we can direct them to or will
     have a better understanding of what is different in your package
     that may cause observed differences from what we expect.

4) We specifically request that you *not* make changes to the margins
   of any paper size in src/xml/papers.xml, or in general change
   papers.xml other than to add additional paper sizes.  In the past,
   a number of distributions have imposed margins for certain paper
   sizes in this file because printing on certain printers was cut off
   (cropped).  Change to papers.xml to work around these problems is
   not an appropriate workaround for this problem, as it results in
   *all* printers being bound by those margins.  Furthermore, the
   margin problem has since been fixed in a different way.  Margins
   should only be listed in papers.xml for papers that intrinsically
   have margins of their own, such as photo papers with tear-off
   margins.

   Historically, in Gutenprint 5.0.0 all printers that offered
   different margins under different circumstances (e. g. a choice
   between normal margins and full-bleed printing, such as many Epson
   inkjet printers, or different margins for certain paper sizes, such
   as many laser printers that offer different margins for A4 than for
   other paper sizes) always listed the wide margins in the PPD files,
   and if the full bleed option was not selected (or a paper size that
   required narrower margins was), the printed image was simply
   clipped to the margins.  This preserved the image dimension on the
   page, but in some cases resulted in parts of the image being
   clipped.  The workaround that some packagers applied, to add
   margins in papers.xml, made it impossible to print full bleed to
   these paper sizes even on printers capable of this.  None of these
   packagers ever discussed this change with us, and as a result we
   were caught by surprise by some bug reports that it took us a while
   to track down.

   This issue was fixed in 5.0.1 (in the native CUPS driver) by means
   of a new PPD option to allow users to either shrink the image to
   the appropriate margins or to crop the image.  This allows users to
   select whether they prefer dimensional accuracy or printing the
   entire image.  However, we have observed that this workaround has
   still not been removed from all distributors' packages.

   At this point, there should be no reason to specify margins in
   papers.xml for any reason other than adding a media size that has
   intrinsic margins of its own, such as a new paper with tear-off
   margins.  If you think you need to do this for any other reason,
   please discuss it with us first!

5) Packaging the Core Library (libgutenprint)

   * You may wish to create a development package containing header
     files and linkable libraries separate from the runtime package.
     There are a few third party applications that link against
     Gutenprint.

   * Gutenprint permits installation of Gimp-Print 4.2 and Gutenprint
     5.0 alongside Gutenprint 5.2, and in the future will permit
     concurrent installation of different stable versions of
     Gutenprint with different minor version numbers.  Therefore, you
     may consider allowing Gutenprint 5.0, Gutenprint 5.2, and
     Gimp-Print 4.2 to be installed concurrently.

   * The core driver library component also includes XML data files
     (in src/xml), locale files for the library, and documentation.
     The XML data files in src/xml are mandatory; the driver will not
     function without these files.

   * We do not recommend installing any program linked against
     libgutenprint with enhanced privileges (via the setuid or setgid
     mechanism, or any other such mechanism).  We have not audited
     libgutenprint for safety in this kind of environment, and changes
     in Gutenprint 5.2 (in particular, moving the Epson driver data
     into external data files whose root can be changed by means of
     the environment variable STP_DATA_PATH) may increase risk.
     Furthermore, if you build the Gutenprint library in modular
     fashion, such that drivers may be dynamically loaded into running
     applications, there is an additional hazard in the form of an
     environment variable that allows specifying where those modules
     should be loaded from (STP_MODULE_PATH).

     The only program in the core Gutenprint package that has any
     reason to be installed this way is escputil, because it needs to
     talk directly to the printer.  See the discussion of escputil
     below.

6) Packaging the CUPS Driver

   * IMPORTANT: As a special part of the install/upgrade procedure,
     your installer should check for any queues using the "epson" or
     "canon" backends and convert them to use an appropriate standard
     backend, usually the "usb" or "parallel" backend.  Please see the
     Critical Upgrade Note in the release notes (NEWS file) for more
     information.

     Note that the epson and canon backends are no longer distributed
     by Gutenprint, so your installer will have to fix this up in any
     event.

   * We recommend that your installation package run cups-genppdupdate
     and restart CUPS as part of the installation process.  This will
     copy changes made by the user and ensure that the user has
     correct PPD files.  The CUPS driver will refuse to use a PPD file
     built with a different version of Gutenprint.

   * Some applications do not translate PPD file contents (option
     names and values) when globalized PPD files are used (see the
     release notes for general discussion of globalized PPD files).
     At the time these notes are being written, we have determined
     that versions of OpenOffice.org up to and including 3.0.0-rc1 do
     not translate PPD file contents with globalized PPD files, but
     language-specific localized PPD files are translated correctly.
     We have also determined that GIMP 2.4, using the GtkPrint plugin,
     does not translate PPD contents using globalized PPD files, but
     does with single language files.

     The CUPS development team has informed us that they have not
     received complaints from users about this, despite the fact that
     the basic set of PPD files distributed by CUPS is globalized.
     Unlike Gutenprint, however, CUPS does not require that its PPD
     files be upgraded with each release, so users upgrading from
     older versions of CUPS may not be exposed to this issue.

     Gutenprint does provide a way to upgrade PPD files to
     language-specific ones, using the -l option to
     cups-genppdupdate.  PPD files that are being upgraded from a
     previous release of Gutenprint may be upgraded with
     cups-genppdupdate -loriginal to update to the original language.
     Note that this works even if the PPD files have been updated to
     globalized files, since cups-genppdupdate stores the language of
     the PPD file it was upgrading.  cups-genppdupdate -l<language>
     updates PPD files into the specified language; see the release
     notes or user's manual for the set of languages supported.

     Note that -loriginal will *not* work with PPD files that had been
     upgraded with Gutenprint 5.2.0-beta4, since cups-genppdupdate in
     that release does not preserve the original language of the PPD
     file.

     Distributions have a number of possible options to address this
     issue, for example:

     - Use globalized PPD files and accept the translation problem or
       fix the applications that do not translate the PPD files
       correctly.  You may wish to document the procedure of using
       cups-genppdupdate to generate language-specific PPD files in
       this case.

     - Configure Gutenprint with --disable-globalized-cups-ppds, to
       generate only single-language PPD files.

     - Provide an administrative utility to update either individual
       PPD files or all PPD files on the system.  If you provide this
       kind of utility, we recommend using the -l<language> option
       rather than -loriginal.

   * All files and directories with versioned names (such as
     rastertogutenprint and the PPD files) may be installed and used
     concurrently with other versions of Gimp-Print and Gutenprint as
     described above.  Other executables (such as cups-calibrate) are
     not versioned, but are not linked against libgutenprint and do
     not have any other dependencies on Gutenprint.

   * Gutenprint includes a custom CUPS backend is necessary to print 
     with many USB-attached dye-sublimation printer models. Strictly 
     speaking this is optional, but without it, many printer models will 
     not function correctly, and as such we recommend it be packaged
     with the Gutenprint CUPS driver.

7) Packaging the Enhanced Print Plugin for GIMP

   * The enhanced Print plugin for GIMP, unlike the core library and
     CUPS drivers, may not be installed concurrently with other
     versions.  For example, you may not install both the Gimp-Print
     4.2 and the Gutenprint 5.2 version of the Print plugin, as they
     use different configuration file formats.

8) Packaging the Epson Inkjet Management Utility, escputil

   * We do not recommend installing this utility with enhanced
     privileges (via the setuid or setgid mechanism, or any other such
     mechanism) without a careful security audit on your part.  If
     elevated privileges are required in your installation, we suggest
     ensuring that the variables STP_DATA_PATH and STP_MODULE_PATH be
     cleared prior to invoking escputil (or that you patch escputil to
     clear those variables prior to calling stp_init()) and otherwise
     using the least privilege required to allow escputil to run.
     Another option may be to allow (by means of device permissions)
     an appropriate group of users to run this command.

     With the conversion of the Epson driver to using external data
     files in XML format rather than data hard-coded into the library
     binary, there are more opportunities for injection of bad data
     into the driver.

     Note that the default configuration of Gutenprint does not
     install escputil with elevated privileges.
