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    <!ENTITY xmllint "<command>xmllint</command>">
]>

<refentry>

<refentryinfo>
    <title>xmllint Manual</title>
    <productname>xmllint</productname>
    <copyright>
        <year>2001</year>
        <year>2004</year>
    </copyright>
    <authorgroup>
        <author>
            <firstname>John</firstname>
            <surname>Fleck</surname>
            <contrib></contrib>
            <affiliation>
                <address>
                    <email>jfleck@inkstain.net</email>
                </address>
            </affiliation>
        </author>
        <author>
            <firstname>Ziying</firstname>
            <surname>Sherwin</surname>
            <contrib></contrib>
            <affiliation>
                <address>
                    <email>sherwin@nlm.nih.gov</email>
                </address>
            </affiliation>
        </author>
        <author>
            <firstname>Heiko</firstname>
            <surname>Rupp</surname>
            <contrib></contrib>
            <affiliation>
                <address>
                    <email>hwr@pilhuhn.de</email>
                </address>
            </affiliation>
        </author>
    </authorgroup>
    <!-- still a bit buggy output, will talk to docbook-xsl upstream to fix this -->
    <!-- <releaseinfo>This is release 0.5 of the xmllint Manual.</releaseinfo> -->
    <!-- <edition>0.5</edition> -->
</refentryinfo>

<refmeta>
    <refentrytitle>xmllint</refentrytitle>
    <manvolnum>1</manvolnum>
</refmeta>

<refnamediv>
    <refname>xmllint</refname>
    <refpurpose>command line <acronym>XML</acronym> tool</refpurpose>
</refnamediv>

<refsynopsisdiv>
    <cmdsynopsis>
    <command>xmllint</command>
        <group choice="opt">
            <arg choice="plain"><option>--version</option></arg>
            <arg choice="plain"><option>--debug</option></arg>
            <arg choice="plain"><option>--quiet</option></arg>
            <arg choice="plain"><option>--shell</option></arg>
            <arg choice="plain"><option>--xpath "<replaceable class="option">XPath_expression</replaceable>"</option></arg>
            <arg choice="plain"><option>--copy</option></arg>
            <arg choice="plain"><option>--recover</option></arg>
            <arg choice="plain"><option>--huge</option></arg>
            <arg choice="plain"><option>--nocompact</option></arg>
            <arg choice="plain"><option>--nodefdtd</option></arg>
            <arg choice="plain"><option>--nodict</option></arg>
            <arg choice="plain"><option>--noenc</option></arg>
            <arg choice="plain"><option>--noent</option></arg>
            <arg choice="plain"><option>--nofixup-base-uris</option></arg>
            <arg choice="plain"><option>--noout</option></arg>
            <arg choice="plain"><option>--nonet</option></arg>
            <arg choice="plain"><option>--path "<replaceable class="option">PATH(S)</replaceable>"</option></arg>
            <arg choice="plain"><option>--load-trace</option></arg>
            <arg choice="plain"><option>--valid</option></arg>
            <arg choice="plain"><option>--postvalid</option></arg>
            <arg choice="plain"><option>--dtdvalid <replaceable class="option">URL</replaceable></option></arg>
            <arg choice="plain"><option>--dtdvalidfpi <replaceable class="option">FPI</replaceable></option></arg>
            <arg choice="plain"><option>--timing</option></arg>
            <arg choice="plain"><option>--output <replaceable class="option">FILE</replaceable></option></arg>
            <arg choice="plain"><option>--repeat</option></arg>
            <arg choice="plain"><option>--insert</option></arg>
            <arg choice="plain"><option>--strict-namespace</option></arg>
            <arg choice="plain"><option>--compress</option></arg>
            <arg choice="plain"><option>--html</option></arg>
            <arg choice="plain"><option>--xmlout</option></arg>
            <arg choice="plain"><option>--push</option></arg>
            <arg choice="plain"><option>--memory</option></arg>
            <arg choice="plain"><option>--max-ampl <replaceable class="option">INTEGER</replaceable></option></arg>
            <arg choice="plain"><option>--maxmem <replaceable class="option">NBBYTES</replaceable></option></arg>
            <arg choice="plain"><option>--nowarning</option></arg>
            <arg choice="plain"><option>--noblanks</option></arg>
            <arg choice="plain"><option>--nocdata</option></arg>
            <arg choice="plain"><option>--format</option></arg>
            <arg choice="plain"><option>--pretty <replaceable class="option">INTEGER</replaceable></option></arg>
            <arg choice="plain"><option>--encode <replaceable class="option">ENCODING</replaceable></option></arg>
            <arg choice="plain"><option>--dropdtd</option></arg>
            <arg choice="plain"><option>--nsclean</option></arg>
            <arg choice="plain"><option>--catalogs</option></arg>
            <arg choice="plain"><option>--nocatalogs</option></arg>
            <arg choice="plain"><option>--auto</option></arg>
            <arg choice="plain"><option>--xinclude</option></arg>
            <arg choice="plain"><option>--noxincludenode</option></arg>
            <arg choice="plain"><option>--loaddtd</option></arg>
            <arg choice="plain"><option>--dtdattr</option></arg>
            <arg choice="plain"><option>--stream</option></arg>
            <arg choice="plain"><option>--walker</option></arg>
            <arg choice="plain"><option>--pattern <replaceable class="option">PATTERNVALUE</replaceable></option></arg>
            <arg choice="plain"><option>--relaxng <replaceable class="option">SCHEMA</replaceable></option></arg>
            <arg choice="plain"><option>--schema <replaceable class="option">SCHEMA</replaceable></option></arg>
            <arg choice="plain"><option>--schematron <replaceable class="option">SCHEMA</replaceable></option></arg>
            <arg choice="plain"><option>--c14n</option></arg>
            <arg choice="plain"><option>--c14n11</option></arg>
            <arg choice="plain"><option>--exc-c14n</option></arg>
            <arg choice="plain"><option>--pedantic</option></arg>
            <arg choice="plain"><option>--sax</option></arg>
            <arg choice="plain"><option>--sax1</option></arg>
            <arg choice="plain"><option>--oldxml10</option></arg>
        </group>
        <group choice="req">
            <arg choice="plain" rep="repeat"><replaceable>XML-FILE(S)</replaceable></arg>
            <arg choice="plain" rep="norepeat">-</arg>
        </group>
    </cmdsynopsis>
</refsynopsisdiv>

<refsect1 id="description">
    <title>DESCRIPTION</title>
    <para>
        The &xmllint; program parses one or more <acronym>XML</acronym> files,
        specified on the command line as <replaceable>XML-FILE</replaceable>
        (or the standard input if the filename provided
        is <emphasis role="bold">-</emphasis> ). It prints various types of
        output, depending upon the options selected. It is useful for detecting
        errors both in <acronym>XML</acronym> code and in
        the <acronym>XML</acronym> parser itself.
    </para>
    <para>&xmllint; is part of the libxml2 library.</para>
</refsect1>

<refsect1 id="validation-options">
    <title>VALIDATION OPTIONS</title>
    <para>
        Options enabling validation.
    </para>

    <variablelist>

        <varlistentry>
            <term><option>--dtdvalid <replaceable class="option">URL</replaceable></option></term>
            <listitem>
                <para>
                    Use the <acronym>DTD</acronym> specified by
                    an <replaceable>URL</replaceable> for validation.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--dtdvalidfpi <replaceable class="option">FPI</replaceable></option></term>
            <listitem>
                <para>
                    Use the <acronym>DTD</acronym> specified by a Formal Public
                    Identifier <replaceable>FPI</replaceable> for validation, note that this
                    will require a catalog exporting that Formal Public Identifier to work.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--relaxng <replaceable class="option">SCHEMA</replaceable></option></term>
            <listitem>
                <para>
                    Use RelaxNG file named <replaceable class="option">SCHEMA</replaceable>
                    for validation.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--schema <replaceable>SCHEMA</replaceable></option></term>
            <listitem>
                <para>
                    Use a W3C <acronym>XML</acronym> Schema file
                    named <replaceable>SCHEMA</replaceable> for validation.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--schematron <replaceable>SCHEMA</replaceable></option></term>
            <listitem>
                <para>
                    Use a Schematron file
                    named <replaceable>SCHEMA</replaceable> for validation.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--valid</option></term>
            <listitem>
                <para>
                    Determine if the document is a valid instance of the included
                    Document Type Definition (<acronym>DTD</acronym>).
                    A <acronym>DTD</acronym> to be validated against also can be
                    specified at the command line using the <option>--dtdvalid</option>
                    option. By default, &xmllint; also checks to determine if the
                    document is well-formed.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--strict-namespace</option></term>
            <listitem>
                <para>
                    Return an error if the document is well-formed, but has namespace
                    errors.  This enforces namespace-well-formedness.
                </para>
            </listitem>
        </varlistentry>

    </variablelist>
</refsect1>

<refsect1 id="parser-options">
    <title>PARSER OPTIONS</title>
    <para>
        The following options set the respective parser options.
    </para>

    <variablelist>

        <varlistentry>
            <term><option>--dtdattr</option></term>
            <listitem>
                <para>
                    Fetch external <acronym>DTD</acronym> and populate the tree with
                    inherited attributes. Implies <option>--loaddtd</option>.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--huge</option></term>
            <listitem>
                <para>Ignore some hardcoded parser limits.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--loaddtd</option></term>
            <listitem>
                <para>
                    Fetch an external <acronym>DTD</acronym> and external
                    parameter entities.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--max-ampl <replaceable class="option">INTEGER</replaceable></option></term>
            <listitem>
                <para>
                    Set the maximum amplification factor which protects against
                    exponential entity expansion ("billion laughs"). The default value
                    is 5. Documents making heavy use of entity expansion may require a
                    higher value.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--noblanks</option></term>
            <listitem>
                <para>
                    Drop "ignorable" blank spaces. This option is unreliable
                    and shouldn't be used.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--nocatalogs</option></term>
            <listitem>
                <para>Do not use any catalogs.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--nocdata</option></term>
            <listitem>
                <para>Substitute CDATA section by equivalent text nodes.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--nodefdtd</option></term>
            <listitem>
                <para>
                    Do not set default HTML doctype (parser option
                    HTML_PARSE_NODEFDTD).
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--noenc</option></term>
            <listitem>
                <para>
                    Ignore encoding declaration (parser option
                    XML_PARSE_IGNORE_ENC).
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--noent</option></term>
            <listitem>
                <para>
                    Substitute entity values for entity references. By default, &xmllint;
                    leaves entity references in place. This enables loading of
                    external DTDs and entities.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--nofixup-base-uris</option></term>
            <listitem>
                <para>
                    Don't fix xml:base URIs when processing XIncludes
                    (parser option XML_PARSE_NOBASEFIX).
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--nonet</option></term>
            <listitem>
                <para>
                    Do not use the Internet to fetch <acronym>DTD</acronym>s or entities. Has no effect with libxml2 2.15 or later.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--nowarning</option></term>
            <listitem>
                <para>Do not emit warnings from the parser and/or validator.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--nsclean</option></term>
            <listitem>
                <para>Remove redundant namespace declarations.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--oldxml10</option></term>
            <listitem>
                <para>
                    Use deprecated parsing rules before XML 1.0,
                    5th edition.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--pedantic</option></term>
            <listitem>
                <para>Enable additional warnings.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--recover</option></term>
            <listitem>
                <para>
                    Output any parsable portions of an invalid document.
                    Exact behavior is unspecified. Use of this option
                    is discouraged.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--xinclude</option></term>
            <listitem>
                <para>Do XInclude processing.</para>
            </listitem>
        </varlistentry>

    </variablelist>
</refsect1>

<refsect1 id="miscellaneous-options">
    <title>MISCELLANEOUS OPTIONS</title>
    <para>
        Options that don't fall in another category.
    </para>

    <variablelist>

        <varlistentry>
            <term><option>--catalogs</option></term>
            <listitem>
                <para>
                    Use the <acronym>SGML</acronym> catalog(s) from <envar>SGML_CATALOG_FILES</envar>.
                    <acronym>XML</acronym> catalogs are loaded by default.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--dropdtd</option></term>
            <listitem>
                <para>Remove <acronym>DTD</acronym> after parsing.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--html</option></term>
            <listitem>
                <para>Use the <acronym>HTML</acronym> parser.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--path "<replaceable class="option">PATH(S)</replaceable>"</option></term>
            <listitem>
                <para>
                    Use the (space- or colon-separated) list of filesystem paths specified
                    by <replaceable>PATHS</replaceable> to load <acronym>DTD</acronym>s or
                    entities. Enclose space-separated lists by quotation marks.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--quiet</option></term>
            <listitem>
                <para>Don't print informational messages to stderr.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--sax</option></term>
            <listitem>
                <para>
                    Print SAX callbacks for debugging. Can be used
                    for streaming DTD and Schema validation when used
                    with <option>--noout</option>.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--shell</option></term>
            <listitem>
                <para>
                    Run a navigating shell. Details on available commands in shell mode
                    are below (see <xref linkend="shell"/>).
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--stream</option></term>
            <listitem>
                <para>
                    Use streaming <acronym>API</acronym> - useful when used in combination
                    with <option>--relaxng</option> or <option>--valid</option> options
                    for validation of files that are too large to be held in memory.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--version</option></term>
            <listitem>
                <para>
                    Display the version of libxml2 used.
                </para>
            </listitem>
        </varlistentry>

    </variablelist>
</refsect1>

<refsect1 id="output-options">
    <title>OUTPUT OPTIONS</title>
    <para>
        Options controlling output. Except for <option>--noout</option>
        these have no effect in SAX or stream mode.
    </para>

    <variablelist>

        <varlistentry>
            <term><option>--compress</option></term>
            <listitem>
                <para>
                    Turn on <citerefentry>
                <refentrytitle>gzip</refentrytitle>
                <manvolnum>1</manvolnum>
            </citerefentry> compression of output.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--c14n</option></term>
            <term><option>--c14n11</option></term>
            <term><option>--exc-c14n</option></term>
            <listitem>
                <para>
                    Use the W3C <acronym>XML</acronym> Canonicalisation (<acronym>C14N</acronym>) to
                    serialize the result of parsing to <filename class="devicefile">stdout</filename>.
                    It keeps comments in the result.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--encode <replaceable class="option">ENCODING</replaceable></option></term>
            <listitem>
                <para>Output in the given encoding. Note that this works for full document not fragments or result from XPath queries.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--format</option></term>
            <listitem>
                <para>
                    Reformat and reindent the output. The <envar>XMLLINT_INDENT</envar>
                    environment variable controls the indentation. The default value is two
                    spaces &quot;  &quot;).
                </para>
                <para>
                    Especially in the absence of a DTD, this feature has never worked reliably
                    and is fundamentally broken.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--noout</option></term>
            <listitem>
                <para>
                    Suppress output. By default, &xmllint; outputs the result tree.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--output <replaceable class="option">FILE</replaceable></option></term>
            <listitem>
                <para>
                    Define a file path where &xmllint; will save the result of parsing.
                    Usually the programs build a tree and save it
                    on <filename class="devicefile">stdout</filename>, with this option
                    the result <acronym>XML</acronym> instance will be saved onto a file.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--pretty <replaceable class="option">INTEGER</replaceable></option></term>
            <listitem>
                <para>
                    Value 0 means no formatting, 1 means XML_SAVE_FORMAT
                    (same as --format), 2 means XML_SAVE_WSNONSIG.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--xmlout</option></term>
            <listitem>
                <para>
                    Used in conjunction with <option>--html</option>. Usually
                    when <acronym>HTML</acronym> is parsed the document is saved with
                    the <acronym>HTML</acronym> serializer. But with this option the
                    resulting document is saved with the <acronym>XML</acronym>
                    serializer. This is primarily used to
                    generate <acronym>XHTML</acronym> from <acronym>HTML</acronym> input.
                </para>
            </listitem>
        </varlistentry>

    </variablelist>
</refsect1>

<refsect1 id="debug-options">
    <title>DEBUG OPTIONS</title>
    <para>
        The following options can be used to debug the libxml2 library.
        Behavior of these options may change without notice.
    </para>

    <variablelist>

        <varlistentry>
            <term><option>--auto</option></term>
            <listitem>
                <para>Generate a small document for testing purposes.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--copy</option></term>
            <listitem>
                <para>Test the internal copy implementation.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--debug</option></term>
            <listitem>
                <para>
                    Parse a file and output an annotated tree of the
                    in-memory version of the document.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--insert</option></term>
            <listitem>
                <para>
                    Test for valid insertions. DEPRECATED: This feature
                    will be removed.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--load-trace</option></term>
            <listitem>
                <para>
                    Display all the documents loaded during the processing
                    to <filename class="devicefile">stderr</filename>.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--maxmem <replaceable class="option">NNBYTES</replaceable></option></term>
            <listitem>
                <para>
                    Test the parser memory support. <replaceable>NNBYTES</replaceable>
                    is the maximum number of bytes the library is allowed to allocate.
                    This can also be used to make sure batch processing
                    of <acronym>XML</acronym> files will not exhaust the virtual memory
                    of the server running them.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--memory</option></term>
            <listitem>
                <para>Parse from memory.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--nocompact</option></term>
            <listitem>
                <para>
                    Do not generate compact text nodes (parser option
                    XML_PARSE_COMPACT). Only for debugging.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--nodict</option></term>
            <listitem>
                <para>
                    Don't use dictionaries (parser option XML_PARSE_NODICT).
                    Only for debugging.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--noxincludenode</option></term>
            <listitem>
                <para>
                    Do XInclude processing but do not generate XInclude start and end nodes.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--pattern <replaceable class="option">PATTERNVALUE</replaceable></option></term>
            <listitem>
                <para>
                    Used to exercise the pattern recognition engine, which can be used
                    with the reader interface to the parser. It allows to select some
                    nodes in the document based on an XPath (subset) expression. Used
                    for debugging.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--postvalid</option></term>
            <listitem>
                <para>Validate after parsing has completed.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--push</option></term>
            <listitem>
                <para>Use the push mode of the parser.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--repeat</option></term>
            <listitem>
                <para>Repeat 100 times, for timing or profiling.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--sax1</option></term>
            <listitem>
                <para>Use deprecated SAX1 interface (only for debugging).</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--timing</option></term>
            <listitem>
                <para>
                    Output information about the time it takes &xmllint; to perform the
                    various steps.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--walker</option></term>
            <listitem>
                <para>
                    Test the walker module, which is a reader interface but for a
                    document tree, instead of using the reader <acronym>API</acronym> on
                    an unparsed document it works on an existing in-memory tree. Used for
                    debugging.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>--xpath "<replaceable class="option">XPath_expression</replaceable>"</option></term>
            <listitem>
                <para>
                    Run an XPath expression given as argument and print the
                    result. In case of a nodeset result, each node in the
                    node set is serialized in full in the output. In case
                    of an empty node set the "XPath set is empty" result
                    will be shown and exit code 11 will be returned..
                </para>
            </listitem>
        </varlistentry>

    </variablelist>
</refsect1>

<refsect1 id="shell">
    <title>SHELL COMMANDS</title>
    <para>
        &xmllint; offers an interactive shell mode invoked with
        the <option>--shell</option> command. Available commands in shell mode
        include (in alphabetical order):
    </para>
    <variablelist>

        <varlistentry>
            <term><command>base</command></term>
            <listitem>
                <para>Display <acronym>XML</acronym> base of the node.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>bye</command></term>
            <listitem>
                <para>Leave the shell.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>cat <replaceable>NODE</replaceable></command></term>
            <listitem>
                <para>Display the given node or the current one.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>cd <replaceable>PATH</replaceable></command></term>
            <listitem>
                <para>
                    Change the current node to the given path (if unique) or root if no
                    argument is given.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>dir <replaceable>PATH</replaceable></command></term>
            <listitem>
                <para>
                    Dumps information about the node (namespace, attributes, content).
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>du <replaceable>PATH</replaceable></command></term>
            <listitem>
                <para>
                    Show the structure of the subtree under the given path or the current node.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>exit</command></term>
            <listitem>
                <para>Leave the shell.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>help</command></term>
            <listitem>
                <para>Show this help.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>load <replaceable>FILENAME</replaceable></command></term>
            <listitem>
                <para>Load a new document with the given filename.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>ls <replaceable>PATH</replaceable></command></term>
            <listitem>
                <para>List contents of the given path or the current directory.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>pwd</command></term>
            <listitem>
                <para>Display the path to the current node.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>quit</command></term>
            <listitem>
                <para>Leave the shell.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>save <replaceable>FILENAME</replaceable></command></term>
            <listitem>
                <para>
                    Save the current document to the given filename or to the original name.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><option>validate</option></term>
            <listitem>
                <para>Check the document for errors.</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><command>write <replaceable>FILENAME</replaceable></command></term>
            <listitem>
                <para>Write the current node to the given filename.</para>
            </listitem>
        </varlistentry>

    </variablelist>
</refsect1>

<refsect1 id="environment">
    <title>ENVIRONMENT</title>
    <variablelist>

        <varlistentry>
            <term><envar>SGML_CATALOG_FILES</envar></term>
            <listitem>
                <para><acronym>SGML</acronym> catalog behavior can be changed by redirecting
                    queries to the user's own set of catalogs. This can be done by setting
                    the <envar>SGML_CATALOG_FILES</envar> environment variable to a list
                    of catalogs. An empty one should deactivate loading the
                    default catalog.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><envar>XML_CATALOG_FILES</envar></term>
            <listitem>
                <para><acronym>XML</acronym> catalog behavior can be changed by redirecting
                    queries to the user's own set of catalogs. This can be done by setting
                    the <envar>XML_CATALOG_FILES</envar> environment variable to a space-separated
                    list of catalogs. Use percent-encoding to escape spaces or other characters.
                    An empty variable should deactivate loading the default catalog.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><envar>XML_DEBUG_CATALOG</envar></term>
            <listitem>
                <para>Setting the environment variable <envar>XML_DEBUG_CATALOG</envar>
                    to <parameter>non-zero</parameter> using the <command>export</command>
                    command outputs debugging information related to catalog operations.
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><envar>XMLLINT_INDENT</envar></term>
            <listitem>
                <para>Setting the environment variable <envar>XMLLINT_INDENT</envar>
                    controls the indentation. The default value is two spaces &quot;  &quot;.
                </para>
            </listitem>
        </varlistentry>

    </variablelist>
</refsect1>

<refsect1 id="diagnostics">
    <title>DIAGNOSTICS</title>
    <para>
        &xmllint; return codes provide information that can be used when
        calling it from scripts.
    </para>
    <!-- better use segmentedlist element later,
         which is currently only supported in snapshots -->
    <variablelist>

        <varlistentry>
            <term><errorcode>0</errorcode></term>
            <listitem>
                <para>No error</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>1</errorcode></term>
            <listitem>
                <para>Unclassified</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>2</errorcode></term>
            <listitem>
                <para>Error in <acronym>DTD</acronym></para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>3</errorcode></term>
            <listitem>
                <para>Validation error</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>4</errorcode></term>
            <listitem>
                <para>Document isn't well-formed or couldn't be read</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>5</errorcode></term>
            <listitem>
                <para>Error in schema compilation</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>6</errorcode></term>
            <listitem>
                <para>Error writing output</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>7</errorcode></term>
            <listitem>
                <para>
                    Error in pattern (generated when <option>--pattern</option> option is used)
                </para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>9</errorcode></term>
            <listitem>
                <para>Out of memory error</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>10</errorcode></term>
            <listitem>
                <para>XPath evaluation error</para>
            </listitem>
        </varlistentry>

        <varlistentry>
            <term><errorcode>11</errorcode></term>
            <listitem>
                <para>XPath result is empty</para>
            </listitem>
        </varlistentry>

    </variablelist>
</refsect1>

<refsect1 id="seealso">
    <title>SEE ALSO</title>
    <para>
        More information can be found in the libxml2 repo at
        <ulink url="https://gitlab.gnome.org/GNOME/libxml2"/>
    </para>
</refsect1>

</refentry>
