Section: HTML-XML-utils (1)
Updated: 10 Jul 2011Index
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hxindex - insert an index into an HTML document
looks for terms to be indexed in a document, collects them, turns them
into target anchors and creates a sorted index as an HTML list, which
is inserted at the place of a placeholder in the document. The
resulting document is written to standard output.
The index is inserted at the place of a comment of the form
or between two comments of the form
In the latter case, all existing content between the two comments is
Index terms are either elements of type <dfn> or elements with a
class attribute of "index". (For backward compatibility, also
class attributes "index-inst" and "index-def" are
recognized.) <dfn> elements (and class "index-def") are
considered more important than elements with class "index" and
will appear in bold in the generated index.
adds additional classes, that are aliases for "index".
By default, the contents of the element are taken as the index term.
Here are two examples of occurrences of the index term "shoe":
A <dfn>shoe</dfn> is a piece of clothing that...
completed by a leather <span class="index">shoe</span>...
If the term to be indexed is not equal to the contents of the element,
the title attribute can be used to give the correct term:
... <dfn title="shoe">Shoes</dfn> are pieces of clothing that...
... with two leather <span class="index" title="shoe">shoes</span>...
The title attribute must also be used when the index term is a
subterm of another. Subterms appear indented in the index, under their
head term. To define a subterm, use a title attribute with two
exclamation marks ("!!") between the term and the subterm, like this:
<dfn title="shoe!!invention of">...</dfn>
<em class="index" title="shoe!!protective!!steel nosed">...</em>
As the last example above shows, there can be multiple levels of
The title attribute also allows multiple index terms to be
associated with a single occurrence. The multiple terms are separated
with a vertical bar ("|"). Compare the following examples with the
<dfn title="shoe!!invention of|inventions!!shoe">...</dfn>
These two elements both insert two terms into the index. Note that the
second example above combines subterms and multiple terms.
It is possible to run index on a file that already has an index. The
old target anchors and the old index will be removed before being
The following options are supported:
adds an ID attribute to the element that contains the occurrence of a
inserts an <a> element inside it with a name
attribute equal to the ID. This is to allow old browsers that ignore
ID attributes, such as
Netscape 4, to find the target as well. The
option suppresses the <a> element.
This option turns on XML syntax conventions: empty elements will end
in /> instead of > as in HTML.
- -i indexdb
can read an initial index from a file and write the merged collection
of index terms back to that file. This allows an index to span several
option is used to give the name of the file that contains the index.
- -b base
This option is useful in combination with
to give the base URL reference of the document. By default,
will store links to occurrences in the indexdb file in the form
#anchor, but when
is given, the links will look like base#anchor instead.
When used in combination with
the title attributes of the links will contain the title of the document that contains the term. The title is inserted before the
and separated from it with a comma and a space. E.g., if
is called with
hxindex -i termdb -n -base myfile.html myfile.html
and the termdb already contains an entry for "foo" in in section "3.1"
of a document called "file2.html" with title "The foos", then the
generated index will contain an entry such as this:
foo, <a href="file2.html#foo"
title="The foos, section 3.1">3.1</a>
- -c class[,class[,...]]
Normal index terms are recognized because they have a class of
option adds additional, comma-separated class
names that will be considered aliases for "index". E.g.,
will make sure that
is recognized as a term for the index.
By default, the index consists of links with "#" as the anchor text.
causes the link text to consist of the section numbers of the sections
in which the terms occur, falling back to "without number" (see option
below) if no section
number could be found. Section numbers are found by looking for the
nearest preceding start tag with a class of "secno" or "no-num". In
the case of "secno", the contents of that element are taken as the
section number. In the case of "no-num" the section is assumed to have
no number and
will print "without number" instead. These classes are also used by
so it is useful to run
hxnum myfile.html | hxindex -n >mynewfile.html
- -s template
is used, the link will have a title attribute and the
determines what it contains. The default is "section %s", where the %s
is a placeholder for the section number. In other words, the index
will contain entries like this:
term, <a href="#term" title="section 7.8">7.8</a>
hxindex -n -s 'chapter %s'
hxindex -n -s 'part %s'
hxindex -n -s 'hoofdstuk %s' -u 'zonder nummer'
This option is only useful in combination with
- -u phrase
is used to display section numbers, references for which no section
number can be found are shown as
instead. The default is "??".
This option is only useful in combination with
Remove title attributes that were used for the index as well as
the comments that delimit the inserted index. This avoids that
browsers display these attributes. Note that hxindex cannot be
run again on its own output if this option is used. (Mnemonic:
"freeze" or "final".)
Do not ignore trailing punctuation when sorting index terms. E.g., if
two terms are written as
<dfn>foo,</dfn>... <span class=index>foo</span>
will normally ignore the comma and treat them as the same term, but
they are treated as different. This affects trailing commas (,),
semicolons (;), colons (:), exclamations mark (!), question marks (?)
and full stops (.). A final full stop is never ignored if there are
two or more in the term, to protect abbreviations ("B.C.") and
ellipsis ("more..."). This does
affect how the index term is printed (it is always printed as it
appears in the text), only how it is compared to similar
terms. (Mnemonic: "raw".)
The following operand is supported:
The name of an HTML or XML file or the URL of one. If absent, or if
the file is "-", standard input is read instead.
The following exit values are returned:
An error occurred in parsing the HTML file.
The input is assumed to be in UTF-8, but the current locale is used to
determine the sorting order of the index terms. I.e.,
looks at the LANG, LC_ALL and/or LC_COLLATE environment variables. See
To use a proxy to retrieve remote files, set the environment variables
Assumes UTF-8 as input. Doesn't expand character entities (apart from
the standard ones: "&", "<", ">" and """). Instead, pipe
the input through
and, if needed,
to convert it to UTF-8.
Remote files (specified with a URL) are currently only supported for
HTTP. Password-protected files or files that depend on HTTP "cookies"
are not handled. (You can use tools such as
to retrieve such files.)
The accessibility of an index, even when generated with option
- EXIT STATUS
- SEE ALSO