returnvalue — The value returned by a function
returnvalue ::=
altanchorannotationbibliorefindexterm (db.indexterm.endofrange)indexterm (db.indexterm.singular)indexterm (db.indexterm.startofrange)inlinemediaobjectlinkolinkphrase (db._phrase)remarkreplaceablesubscriptsuperscriptxrefReturnValue identifies the value returned by a
function or command.  
These elements contain returnvalue: bridgehead, citation, citetitle, classsynopsisinfo, emphasis (db.emphasis), entry, firstterm, funcsynopsisinfo, glosssee, glossseealso, glossterm, html:button, html:label, html:legend, link, literallayout, member, olink, orgdiv, para, phrase (db.phrase), primary, primaryie, programlisting, quote, refdescriptor, refentrytitle, refname, refpurpose, screen, secondary, secondaryie, see, seealso, seealsoie, seeie, seg, segtitle, simpara, subtitle, synopsis, td, term, termdef, tertiary, tertiaryie, th, title, titleabbrev, tocentry.
The following elements occur in returnvalue: text, alt, anchor, annotation, biblioref, indexterm (db.indexterm.endofrange), indexterm (db.indexterm.singular), indexterm (db.indexterm.startofrange), inlinemediaobject, link, olink, phrase (db._phrase), remark, replaceable, subscript, superscript, xref.
funcdef, funcparams, funcprototype, funcsynopsisinfo, function, paramdef, parameter, varargs, void<article xmlns='http://docbook.org/ns/docbook'> <title>Example returnvalue</title> <para>The <function>open</function> function returns <returnvalue>2</returnvalue> (<errorname>ENOFILE</errorname>) if the file does not exist. </para> </article>
The open function returns 2
(ENOFILE) if the file does not exist.