DocBook Publishers: The Definitive Guide  (Version 1.2.1 for DocBook 5.1)

optional

optional — Optional information.

Synopsis

optional ::= [-]

Description

The optional element indicates that a specified argument, option, or other text is optional. The precise meaning of “optional” varies according to the application or process being documented.

Processing expectations

Formatted inline.

Parents

These elements contain optional: bridgehead, citation, citetitle, contrib, emphasis (db.emphasis), entry, firstterm (db.firstterm), glosssee, glossseealso, glossterm (db.glossterm), line, link, literallayout, member, olink, orgdiv, para, phrase (db.phrase), primary, quote (db.quote), remark, secondary, see, seealso, simpara, subtitle, term, termdef, tertiary, title, titleabbrev.

Children

The following elements occur in optional: text, abbrev, acronym, alt, anchor, biblioref, coref, date, emphasis (db._emphasis), firstterm (db._firstterm), footnote, footnoteref, foreignphrase (db._foreignphrase), glossterm (db._glossterm), indexterm (db.indexterm.endofrange), indexterm (db.indexterm.singular), indexterm (db.indexterm.startofrange), inlinemediaobject, link, olink, phrase (db._phrase), quote (db._quote), remark, subscript, superscript, trademark, wordasword, xref.

See Also

Examples

<article xmlns='http://docbook.org/ns/docbook'>
<title>Example optional</title>

<synopsis>
ls <option>-abcCdfFgilLmnopqrRstux1</option>
   <optional>names</optional>
</synopsis>

</article>

ls -abcCdfFgilLmnopqrRstux1
   names