Name

xmllint — command line XML tool

Synopsis

xmllint [[--version] | [--debug] | [--shell] | [--debugent] | [--copy] | [--recover] | [--noent] | [--noout] | [--nonet] | [--htmlout] | [--nowrap] | [--valid] | [--postvalid] | [--dtdvalid URL] | [--dtdvalidfpi FPI] | [--timing] | [--output file] | [--repeat] | [--insert] | [--compress] | [--html] | [--xmlout] | [--push] | [--memory] | [--maxmem nbbytes] | [--nowarning] | [--noblanks] | [--nocdata] | [--format] | [--encode encoding] | [--dropdtd] | [--nsclean] | [--testIO] | [--catalogs] | [--nocatalogs] | [--auto] | [--xinclude] | [--noxincludenode] | [--loaddtd] | [--dtdattr] | [--stream] | [--walker] | [--pattern patternvalue] | [--chkregister] | [--relaxng] | [--schema] | [--c14n]] [xmlfile]

Introduction

The xmllint program parses one or more XML files, specified on the command line as xmlfile. It prints various types of output, depending upon the options selected. It is useful for detecting errors both in XML code and in the XML parser itself.

It is included in libxml2.

Options

--version
Display the version of libxml2 used.
--debug
Parse a file and output an annotated tree of the in-memory version of the document.
--shell
Run a navigating shell. Details on available commands in shell mode are below.
--debugent
Debug the entities defined in the document.
--copy
Test the internal copy implementation.
--recover
Output any parsable portions of an invalid document.
--noent
Substitute entity values for entity references. By default, xmllint leaves entity references in place.
--nocdata
Substitute CDATA section by equivalent text nodes.
--nsclean
Remove redundant namespace declarations.
--noout
Suppress output. By default, xmllint outputs the result tree.
--htmlout
Output results as an HTML file. This causes xmllint to output the necessary HTML tags surrounding the result tree output so the results can be displayed in a browser.
--nowrap
Do not output HTML doc wrapper.
--valid
Determine if the document is a valid instance of the included Document Type Definition (DTD). A DTD to be validated against also can be specified at the command line using the --dtdvalid option. By default, xmllint also checks to determine if the document is well-formed.
--postvalid
Validate after parsing is completed.
--dtdvalid URL
Use the DTD specified by URL for validation.
--dtdvalidfpi FPI
Use the DTD specified by the Public Identifier FPI for validation, note that this will require a Catalog exporting that Public Identifier to work.
--timing
Output information about the time it takes xmllint to perform the various steps.
--output file
Define a file path where xmllint will save the result of parsing. Usually the programs build a tree and save it on stdout, with this option the result XML instance will be saved onto a file.
--repeat
Repeat 100 times, for timing or profiling.
--insert
Test for valid insertions.
--compress
Turn on gzip compression of output.
--html
Use the HTML parser.
--xmlout
Used in conjusntion with --html. Usually when HTML is parsed the document is saved with the HTML serializer, but with this option the resulting document is saved with the XML serializer. This is primarily used to generate XHTML from HTML input.
--push
Use the push mode of the parser.
--memory
Parse from memory.
--maxmem nnbytes
Test the parser memory support. nnbytes is the maximum number of bytes the library is allowed to allocate. This can also be used to make sure batch processing of XML files will not exhaust the virtual memory of the server running them.
--nowarning
Do not emit warnings from the parser and/or validator.
--noblanks
Drop ignorable blank spaces.
--format
Reformat and reindent the output. The $XMLLINT_INDENT environment variable controls the indentation (default value is two spaces " ").
--testIO
Test user input/output support.
--encode encoding
Output in the given encoding.
--catalogs
Use the catalogs from $SGML_CATALOG_FILES. Otherwise /etc/xml/catalog is used by default.
--nocatalogs
Do not use any catalogs.
--auto
Generate a small document for testing purposes.
--xinclude
Do XInclude processing.
--noxincludenode
Do XInclude processing but do not generate XInclude start and end nodes.
--loaddtd
Fetch external DTD.
--dtdattr
Fetch external DTD and populate the tree with inherited attributes.
--dropdtd
Remove DTD from output.
--stream
Use streaming API - useful when used in combination with --relaxng or --valid options for validation of files that are too large to be held in memory.
--walker
Test the walker module, which is a reader interface but for a document tree, instead of using the reader API on an unparsed document it works on a existing in-memory tree. Used in debugging.
--chkregister
Turn on node registration. Useful for developers testing libxml2 node tracking code.
--pattern patternvalue
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.
--relaxng schema
Use RelaxNG file named schema for validation.
--schema schema
Use a W3C XML Schema file named schema for validation.
--c14n
Use the W3C XML Canonicalisation (C14N) to serialize the result of parsing to stdout. It keeps comments in the result.

Shell

xmllint offers an interactive shell mode invoked with the --shell command. Available commands in shell mode include:

base
display XML base of the node
bye
leave shell
cat node
Display node if given or current node.
cd path
Change the current node to path (if given and unique) or root if no argument given.
dir path
Dumps information about the node (namespace, attributes, content).
du path
Show the structure of the subtree under path or the current node.
exit
Leave the shell.
help
Show this help.
free
Display memory usage.
load name
Load a new document with the given name.
ls path
List contents of path (if given) or the current directory.
pwd
Display the path to the current node.
quit
Leave the shell.
save name
Saves the current document to name if given or to the original name.
validate
Check the document for error.
write name
Write the current node to the given filename.

Catalogs

Catalog behavior can be changed by redirecting queries to the user's own set of catalogs. This can be done by setting the XML_CATALOG_FILES environment variable to a list of catalogs. An empty one should deactivate loading the default /etc/xml/catalog default catalog.

Debugging Catalogs

Setting the environment variable XML_DEBUG_CATALOG using the command "export XML_DEBUG_CATALOG=" outputs debugging information related to catalog operations.

Error Return Codes

On the completion of execution, Xmllint returns the following error codes:

0
No error
1
Unclassified
2
Error in DTD
3
Validation error
4
Validation error
5
Error in schema compilation
6
Error writing output
7
Error in pattern (generated when [--pattern] option is used)
8
Error in Reader registration (generated when [--chkregister] option is used)
9
Out of memory error