NAME¶
rxp - XML parser program
SYNOPSIS¶
rxp [
-abemnNRsStvVx4 ] [
-o b|p|0|1|2|3|i|d ] [
U
0|1|2 ] [
-c encoding ] [
url ]
DESCRIPTION¶
rxp reads and parses XML from the
url (or standard input if none
is provided) and writes it to standard output, optionally expanding entities,
defaulting attributes, and translating to a different output encoding.
rxp accepts XML 1.0 and 1.1, and the corresponding versions of XML
namespaces. It implements the Oasis XML catalog specification.
Common option combinations are
-Nxs to check a document for
well-formedness and namespace well-formedness, and
-VNxs to also check
for DTD-validity.
OPTIONS¶
- -a
- Insert declared default values for omitted attributes.
- -v
- Be verbose.
- -V
- Validate the document. Repeating this option will make the
program treat validity errors as well-formedness errors, and exit after
the first validity error (otherwise a warning will be printed for each
one).
- -d
- Read the whole DTD (internal and external parts) regardless
of any standalone declaration. Otherwise a declaration
"standalone='yes'" will prevent the external part from being
read (unless validation is selected).
- -N
- Enable XML namespace support. The document will be checked
for correct namespace syntax, and if -b is specified qualified
element and attribute names will be displayed with their URIs.
- -R
- The value of this flag is a time limit in seconds, after
which the program will abort. This is to protect against denial-of-service
attacks using malicious documents.
- -S
- Keep track of xml:space attributes. This will only affect
output when -b is specified.
- -e
- Obsolete, do not use.
- -E
- Do not expand entity references (opposite of old -e
flag)
- -s
- Be silent (that is, suppress output). Useful for
benchmarking or if you just want to see the error messages.
- -b
- Print output as "bits".
- -n
- Treat the input as normalised SGML rather than XML. Not
intended for general use.
- -o
- If this flag is p, output is in the default (plain)
format. If it is b, output is printed as "bits"
(equivalent to -b). If it is 0, output is suppressed
(equivalent to -s). If it is 1, 2 or 3, output
is in first, second or third canonical form. If it is i, output is
a dump of the document's infoset. If it is d, output is in a form
suitable for use with "diff"; in particular attributes are
sorted into alphabetical order.
- -m
- Merge PCData across entity references. This will only
affect the output when -b is specified.
- -t
- Read in the input as a tree, rather than bits. Should make
no difference to the output.
- -u base_uri
- Use the specified base URI when resolving system
identifiers.
- -U
- This flag controls Unicode normalization checking and is
only relevant when parsing XML 1.1 documents. If it is 0, no
checking is done. If it is 1, rxp checks that the document
is fully normalized as defined by the W3C character model. If it is
2, the document is checked and any unknown characters (which may be
ones corresponding to a newer version of Unicode than rxp knows
about) will also cause an error.
- -x
- Strict XML mode. This suppresses some warnings (eg entity
redefinitions) but treats all XML well-formedness errors as fatal. This
flag implies the -a flag, and sets the output encoding to UTF-8
unless the -c flag is given. It sets the output format to first
canonical form unless the -o, -b or -s flag is
given.
- -c encoding
- Produce output in the specified character encoding. Known
encodings include ISO-8859-1, UTF-8, ISO-10646-UCS
and UTF-16. 16-bit encoding names my be suffixed with -B or
-L to specify big- or little-endian byte order (the default is the
host byte order). If no -c or -x option is given, output is
in the same encoding as the input document.
- -D name sysid
- Force use of the document type specified by sysid.
The root element name for validation is name. Any DTD in the
document is ignored. This flag does not imply validation; use -V if
required.
- -i
- Do xml:id processing. Attributes named xml:id are
recognised as IDs even if not declared.
- -I
- The same as -i, but in addition xml:id attributes
are checked for uniqueness.
- -z
- Use a shorter format for error messages. Particularly
useful when using the parser in Emacs compilation mode, so that Emacs can
find the error location.
- -4
- Use pre-fifth-edition rules for XML 1.0. XML 1.0 fifth
edition extends the set of allowed name characters to match XML 1.1, and
allows unrecognised version numbers of the form 1.x to be treated as 1.0.
the -4 flag disables these changes.
EXIT STATUS¶
If the
-V flag is given, and the document is well-formed but not valid, 2
is returned. If the document is not well-formed, or a system error occurs, 1
is returned. Otherwise 0 is returned. Since the parser can expand external
entities even when not validating, it treats certain errors which are
technically validity errors as well-formedness errors. If
-x is not
specified, some well-formedness errors produce only warnings and do not affect
the exit status.
ENVIRONMENT¶
If the environment variable
XML_CATALOG_FILES is set, XML catalog
processing is enabled. A catalog can be used to map system and public
identifiers to local files. In particular, this allows copies of common DTDs
to be kept locally, so that
rxp does not have to fetch them over the
internet.
XML_CATALOG_FILES should be set to a space-separated list of
catalog files. The variable
XML_CATALOG_PREFER may be set to
public or
system to set the initial mode for catalog processing;
the default is
system.
If the variable
RXPURL is set, it is used as the URL of the document to
parse. This may be useful in CGI scripts and the like to avoid shell parsing
of a user-supplied argument.
The variable
http_proxy can be used to specify a proxy for HTTP
connections. The syntax is
hostname[:port].