getconfig(4)

NAME

       getconfig - meta configuration files for getconfig(1)

SYNOPSIS

       *.cfg

DESCRIPTION

       getconfig is a programatic interface that is used by the Xorg server to
       get configuration information about video hardware when operating with-
       out an xorg.conf file.

       This  implementation  of  getconfig  is  written in perl.  It processes
       rules from meta-configuration files.  All meta-configuration files have
       a .cfg suffix.

       Lines  starting  with  a  pound-sign (#) are comments, and are ignored.
       Blank lines that consist only of white space are also treated  as  com-
       ments and ignored.

       The  first  non-comment line must be a signature string followed by the
       file format version number.  The signature string is

           "Xorg getconfig rules file.  Version: "

       The currently defined version is "1.0".  Files that  do  not  have  the
       correct signature string are ignored.

       The  remaining non-comment lines define rules.  The start of a new rule
       is indicated by a line with no leading white space.   Subsequent  lines
       making  up  a  rule  must  be indented with white space.  Logical lines
       within a rule may be split over multiple physical lines  by  using  the
       usual  continuation convention ('\' at the end of the line).  The first
       logical line of each rule is a perl expression.  It may  be  any  valid
       perl expression whose evaluated (with 'eval') result may be used as the
       argument to a perl 'if' statement.  The second logical line  should  be
       the  name  of  the  Xorg video driver to use when the rule is true, and
       subsequent logical lines of each rule, if present, are additional  con-
       figuration output for the video device's xorg.conf Device section.  The
       driver name and additional lines of configuration information are writ-
       ten  to standard output when the rule is chosen as the successful rule.

       Pseudo rules consisting of perl expressions may be present in the  file
       for the purpose of defining custom perl variables or setting the weight
       to use for the following rules.  Pseudo rules are rules that consist of
       a single logical line only, and the are never candidates themselves for
       the successful rule.

       Several perl variables are pre-defined, and may be used  within  rules.
       They include:

           $vendor                 PCI vendor ID
           $device                 PCI device ID
           $revision               PCI revision ID
           $subsys                 PCI subsystem ID
           $subsysVendor           PCI subsystem vendor ID
           $class                  PCI class
           $XorgVersion         Xorg version, as a 'v' string
           $XorgVersionNumeric  Xorg numeric version
           $XorgVersionMajor    Xorg major version
           $XorgVersionMinor    Xorg minor version
           $XorgVersionPatch    Xorg patch version
           $XorgVersionSnap     Xorg snap version
           $weight                 current rule weight

       The $weight variable deterines the weight of the rules as they are pro-
       cessed.  The weight for subsequent rules may be set with a pseudo  rule
       that sets or changes the value of $weight.  The default weight, and the
       weight used for built-in rules is 500.   The  meta-configuration  files
       are processed in an unpredictable order.  The weighting of the rules is
       used to determine their relative priority

       After processing all of the rules, both built-in and  those  read  from
       the  meta-configration files, the getconfig program chooses as the suc-
       cessful rule the last and highest weighted rule that evaluates to true.

FILES

       .cfg files located in the search path.  The search path typically spec-
       ified by the Xorg server is:

           /etc/X11
           /usr/X11R6/etc/X11
           <modulepath>
           /usr/X11R6/lib/X11/getconfig

       where <modulepath> is the Xorg server's module search path.

       /usr/X11R6/lib/X11/getconfig/xorg.cfg
                                     Default rules file that  gets  installed.
                                     This  file  doesn't  contain any rules by
                                     default.

       /usr/X11R6/lib/X11/getconfig/cfg.sample
                                     A sample rules file that gives some exam-
                                     ples of what types of rules can appear in
                                     rules files.

SEE ALSO

       getconfig(1), Xorg(1), xorg.conf(4).

AUTHORS

       The Xorg automatic configuration support and  the  getconfig  interface
       was  written  by  David H. Dawes, with the support of X-Oz Technologies
       for XFree86.

X.Org                            Version 6.8.2                    getconfig(4)