noble (7) frontend-spec.7.gz

NAME

       frontend-spec - interface between jw and its frontends

DESCRIPTION

       jw(1)  calls  frontends  like frontends/docbook to get the informations specific to a given input format.
       The frontend knows which information to return from  the  first  command  line  parameter.  It  gets  all
       necessary data via environment variables ready to use.

       This document describes that command line parameter and those environment variables.

       The frontend should return 0 if there weren't any problem, and return a positive value otherwise.

VARIABLES

                 $1
              The  command  line  parameter,  specifying  which information to return. It can take the following
              values:

              centralized-catalog
                     The frontend must return the DTD-specific centralized catalog name.   Centralized  catalogs
                     normally  reside  in /etc/sgml and provide the location of all the catalog files useful for
                     handling this input type (the catalog for the DTD, the catalog  for  the  stylesheets,  the
                     catalog for the entities, ...)

              style-sheet
                     The  frontend must return the filename of the style sheet to be used for this document type
                     and with the chosen backend.

                 SGML_CATALOGS_DIR
              The directory where the centralized catalogs reside. It is normally /etc/sgml.

              (This variable is valid only while determining the centralized catalog to use.)

                 SGML_BASE_DIR
              The base directory of the SGML system. It is normally /usr/share/sgml.

              (This variable is valid only while determining the style sheet to use.)

                 SGML_FILE
              The name of the file to convert.

              (This variable is valid only while determining the centralized catalog to use.)

                 SGML_TYPE
              The type of the backend to use, whether it produces output files to be displayed online or  to  be
              printed out.  It can take the value html or print.

              (This variable is valid only while determining the style sheet to use).

                 SGML_STYLESHEETS
              The desired custom stylesheet type, either none or default.  If none, the frontend must return the
              file name of the style sheet provided by the system beneath the docbook-utils.   If  default,  the
              frontend must return the custom stylesheet provided by the docbook-utils.

              (This variable is valid only while determining the style sheet to use).

                 SGML_XML
              The metalanguage of the file to convert, either sgml or xml.

              (This variable is valid only while determining the centralized catalog to use).

FILES

SEE ALSO

       backend-spec(7)

AUTHORS

       Jochem Huhmann <joh@revier.com>

                                                 14 January 2022                                FRONTEND-SPEC(7)