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 conjunction 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
