frontend-spec (7)

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.

$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).

backend-spec(7)

Jochem Huhmann <[email protected]>