NAME
xref - generate cross-references inside and between
HTML files
SYNOPSIS
xref [ -x ] [ -b base
] [ -i index ] [ -- ] [ input [ output
] ]
DESCRIPTION
The xref command links inline elements to DFN elements
with the same content. It adds ID attributes where necessary. If
the content of a DFN or other element isn't suitable, the TITLE
attribute may be used to provide the term to use for comparisons.
Here is an example:
<p>A <dfn>b-box</dfn> is defined to be...
<p>For every b there is a <em>b-box</em>...
The output of xref will be similar to this:
<p>A <dfn id="b-box">b-box</dfn> is defined to be...
<p>For every b there is a <em><a href="#b-box">b-box<a/></em>...
OPTIONS
The following options are supported:
- -x
- Use XML conventions: empty elements are written with a slash at
the end: <IMG />
- -b base
- Sets the prefix for the generated URLs. By default base
is empty, which generates URLs like "#b-box" above. If base
is set to, e.g., "http://xyz/", the URLs
will look like "http://xyz/#b-box".
- -i index
- Directs xref to read terms from a database file before
looking for them in the document and afterwards store the terms
that were found in the same file. DFN element in the document
ovrride terms found in index. This allows xref to be
run multiple times on different files, to make the files refer to
each other. It may be necessary to run the commands twice, to
resolve all cross-references.
OPERANDS
The following operands are supported:
- input
- The name of an HTML file. If absent, standard input is read
instead. The special name "-" also indicates standard input. The
input may be a URL.
- output
- The file to write to. If absent, standard output is used. This
may not be a URL.
EXIT STATUS
The following exit values are returned:
- 0
- Successful completion.
- >0
- An error occurred in the parsing of the HTML file. toc
will try to correct the error and produce output
anyway.
SEE ALSO
index(1),
num(1),
toc(1),
normalize(1),
xml2asc(1)
asc2xml(1)
BUGS
The error recovery for incorrect HTML is primitive.
The program generates ID attributes, but doesn't generate <a
name=...> tags, so the links only work in browsers that
recognize ID attributes.