xmlwf [ -s] [ -n] [ -p] [ -x] [ -e encoding] [ -w] [ -d output-dir] [ -c] [ -m] [ -r] [ -t] [ -v] [ file ...]
xmlwf uses the Expat library to determine if an XML document is well-formed. It is non-validating.
If you do not specify any files on the command-line, and you have a recent version of xmlwf, the input file will be read from standard input.
A well-formed document must adhere to the following rules:
If the document has a DTD, and it strictly complies with that DTD, then the document is also considered valid. xmlwf is a non-validating parser -- it does not check the DTD. However, it does support external entities (see the -x option).
When an option includes an argument, you may specify the argument either separately ("-d output") or concatenated with the option ("-doutput"). xmlwf supports both.
The output filenames will be exactly the same as the input filenames or "STDIN" if the input is coming from standard input. Therefore, you must be careful that the output file does not go into the same directory as the input file. Otherwise, xmlwf will delete the input file before it generates the output file (just like running cat < file > file in most shells).
Two structurally equivalent XML documents have a byte-for-byte identical canonical XML representation. Note that ignorable white space is considered significant and is treated equivalently to data. More on canonical XML can be found at http://www.jclark.com/xml/canonxml.html .
Normally xmlwf never parses parameter entities. -p tells it to always parse them. -p implies -x.
Use of memory-mapping can cause some platforms to report substantially higher memory usage for xmlwf, but this appears to be a matter of the operating system reporting memory in a strange way; there is not a leak in xmlwf.
Non-validating parsers are not required to resolve external entities, or even expand entities at all. Expat always expands internal entities (?), but external entity parsing must be enabled explicitly.
External entities are simply entities that obtain their data from outside the XML file currently being parsed.
This is an example of an internal entity:
<!ENTITY vers '1.0.2'>
And here are some examples of external entities:
<!ENTITY header SYSTEM "header-&vers;.xml"> (parsed) <!ENTITY logo SYSTEM "logo.png" PNG> (unparsed)
xmlwf -- -myfile.xml
will run xmlwf on the file -myfile.xml.
Older versions of xmlwf do not support reading from standard input.
If an input file is not well-formed, xmlwf prints a single line describing the problem to standard output. If a file is well formed, xmlwf outputs nothing. Note that the result code is not set.
According to the W3C standard, an XML file without a declaration at the beginning is not considered well-formed. However, xmlwf allows this to pass.
xmlwf returns a 0 - noerr result, even if the file is not well-formed. There is no good way for a program to use xmlwf to quickly check a file -- it must parse xmlwf's standard output.
The errors should go to standard error, not standard output.
There should be a way to get -d to send its output to standard output rather than forcing the user to send it to a file.
I have no idea why anyone would want to use the -d, -c, and -m options. If someone could explain it to me, I'd like to add this information to this manpage.
Here are some XML validators on the web:
http://www.hcrc.ed.ac.uk/~richard/xml-check.html http://www.stg.brown.edu/service/xmlvalid/ http://www.scripting.com/frontier5/xml/code/xmlValidator.html http://www.xml.com/pub/a/tools/ruwf/check.html
The Expat home page: http://www.libexpat.org/ The W3 XML specification: http://www.w3.org/TR/REC-xml
This manual page was written by Scott Bronson <email@example.com> for the Debian GNU/Linux system (but may be used by others). Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1.