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><H1
><A
NAME="FRONTEND-SPEC"
></A
>frontend-spec</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN918"
></A
><H2
>Name</H2
>frontend-spec -- interface between jw and its frontends</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN921"
></A
><H2
>Description</H2
><P
><SPAN
CLASS="CITEREFENTRY"
><SPAN
CLASS="REFENTRYTITLE"
>jw</SPAN
>(1)</SPAN
> calls frontends like
<TT
CLASS="FILENAME"
>frontends/docbook</TT
> 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.</P
><P
>This document describes that command line parameter and those
environment variables.</P
><P
>The frontend should return 0 if there weren't any problem,
and return a positive value otherwise.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN930"
></A
><H2
>Variables</H2
><DIV
CLASS="GLOSSLIST"
><DL
><DT
><B
> <CODE
CLASS="ENVAR"
>$1</CODE
>
</B
></DT
><DD
><P
>The command line parameter, specifying which information
to return. It can take the following values:
<P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
>centralized-catalog</DT
><DD
><P
>The frontend must return the DTD-specific
centralized catalog name. Centralized catalogs normally
reside in <TT
CLASS="FILENAME"
>/etc/sgml</TT
> 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,
...)</P
></DD
><DT
>style-sheet</DT
><DD
><P
>The frontend must return the filename
of the style sheet to be used for this document type and
with the chosen backend.</P
></DD
></DL
></DIV
>
</P
></DD
></DL
></DIV
><P
></P
><DIV
CLASS="GLOSSLIST"
><DL
><DT
><B
> <CODE
CLASS="ENVAR"
>SGML_CATALOGS_DIR</CODE
>
</B
></DT
><DD
><P
>The directory where the centralized catalogs reside. It is normally
<TT
CLASS="FILENAME"
>/etc/sgml</TT
>.</P
><P
>(This variable is valid only while determining
the centralized catalog to use.)</P
></DD
></DL
></DIV
><P
></P
><DIV
CLASS="GLOSSLIST"
><DL
><DT
><B
> <CODE
CLASS="ENVAR"
>SGML_BASE_DIR</CODE
>
</B
></DT
><DD
><P
>The base directory of the SGML system. It is normally
<TT
CLASS="FILENAME"
>/usr/share/sgml</TT
>.</P
><P
>(This variable is valid only while determining
the style sheet to use.)</P
></DD
></DL
></DIV
><P
></P
><DIV
CLASS="GLOSSLIST"
><DL
><DT
><B
> <CODE
CLASS="ENVAR"
>SGML_FILE</CODE
>
</B
></DT
><DD
><P
>The name of the file to convert.</P
><P
>(This variable is valid only while determining
the centralized catalog to use.)</P
></DD
></DL
></DIV
><P
></P
><DIV
CLASS="GLOSSLIST"
><DL
><DT
><B
> <CODE
CLASS="ENVAR"
>SGML_TYPE</CODE
>
</B
></DT
><DD
><P
>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 <CODE
CLASS="CONSTANT"
>html</CODE
> or
<CODE
CLASS="CONSTANT"
>print</CODE
>.</P
><P
>(This variable is valid only while determining
the style sheet to use).</P
></DD
></DL
></DIV
><P
></P
><DIV
CLASS="GLOSSLIST"
><DL
><DT
><B
> <CODE
CLASS="ENVAR"
>SGML_STYLESHEETS</CODE
>
</B
></DT
><DD
><P
>The desired custom stylesheet type, either <CODE
CLASS="CONSTANT"
>none</CODE
>
or <CODE
CLASS="CONSTANT"
>default</CODE
>.
If <CODE
CLASS="CONSTANT"
>none</CODE
>, the frontend must return the file name of
the style sheet provided by the system beneath the docbook-utils.
If <CODE
CLASS="CONSTANT"
>default</CODE
>, the frontend must return the custom
stylesheet provided by the docbook-utils.</P
><P
>(This variable is valid only while determining
the style sheet to use).</P
></DD
></DL
></DIV
><DIV
CLASS="GLOSSLIST"
><DL
><DT
><B
> <CODE
CLASS="ENVAR"
>SGML_XML</CODE
>
</B
></DT
><DD
><P
>The metalanguage of the file to convert, either <CODE
CLASS="CONSTANT"
>sgml</CODE
>
or <CODE
CLASS="CONSTANT"
>xml</CODE
>.</P
><P
>(This variable is valid only while determining
the centralized catalog to use).</P
></DD
></DL
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1005"
></A
><H2
>Files</H2
><P
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1008"
></A
><H2
>See also</H2
><P
><SPAN
CLASS="CITEREFENTRY"
><SPAN
CLASS="REFENTRYTITLE"
>backend-spec</SPAN
>(7)</SPAN
></P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1014"
></A
><H2
>Authors</H2
><P
>Jochem Huhmann <CODE
CLASS="EMAIL"
><<A
HREF="mailto:joh@revier.com"
>joh@revier.com</A
>></CODE
></P
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