Free relaxng software for linux

XML::LibXML::Reader is a Perl interface to libxml2 pull parser.

SYNOPSIS

use XML::LibXML::Reader;

$reader = new XML::LibXML::Reader("file.xml")
or die "cannot read file.xmln";
while ($reader->read) {
processNode($reader);
}


sub processNode {
$reader = shift;
printf "%d %d %s %dn", ($reader->depth,
$reader->nodeType,
$reader->name,
$reader->isEmptyElement);
}
or
$reader = new XML::LibXML::Reader("file.xml")
or die "cannot read file.xmln";
$reader->preservePattern(//table/tr);
$reader->finish;
print $reader->document->toString(1);

This is a perl interface to libxml2s pull-parser implementation xmlTextReader http://xmlsoft.org/html/libxml-xmlreader.html. This feature requires at least libxml2-2.6.21. Pull-parser (StAX in Java, XmlReader in C#) use an iterator approach to parse a xml-file. They are easier to program than event-based parser (SAX) and much more lightweight than tree-based parser (DOM), which load the complete tree into memory.

The Reader acts as a cursor going forward on the document stream and stopping at each node in the way. At every point DOM-like methods of the Reader object allow to examine the current node (name, namespace, attributes, etc.)

The users code keeps control of the progress and simply calls the read() function repeatedly to progress to the next node in the document order. Other functions provide means for skipping complete sub-trees, or nodes until a specific element, etc.

At every time, only a very limited portion of the document is kept in the memory, which makes the API more memory-efficient than using DOM. However, it is also possible to mix Reader with DOM. At every point the user may copy the current node (optionally expanded into a complete sub-tree) from the processed document to another DOM tree, or to instruct the Reader to collect sub-document in form of a DOM tree consisting of selected nodes.

Reader API also supports namespaces, xml:base, entity handling, and DTD validation. Schema and RelaxNG validation support will probably be added in some later revision of the Perl interface.

The naming of methods compared to libxml2 and C# XmlTextReader has been changed slightly to match the conventions of XML::LibXML. Some functions have been changed or added with respect to the C interface.

XMLStarlet is a set of command line utilities (tools) which can be used to transform, query, validate, and edit XML documents and files using simple set of shell commands in similar way it is done for plain text files using UNIX grep, sed, awk, diff, patch, join, etc commands.
This set of command line utilities can be used by those who deal with many XML documents on UNIX shell command prompt as well as for automated XML processing with shell scripts.
Main features:
- Check or validate XML files (simple well-formedness check, DTD, XSD, RelaxNG)
- Calculate values of XPath expressions on XML files (such as running sums, etc)
- Search XML files for matches to given XPath expressions
- Apply XSLT stylesheets to XML documents (including EXSLT support, and passing parameters to stylesheets)
- Query XML documents (ex. query for value of some elements of attributes, sorting, etc)
- Modify or edit XML documents (ex. delete some elements)
- Format or "beautify" XML documents (as changing indentation, etc)
- Fetch XML documents using http:// or ftp:// URLs
- Browse tree structure of XML documents (in similar way to ls command for directories)
- Include one XML document into another using XInclude
- XML c14n canonicalization
- Escape/unescape special XML characters in input text
- Print directory as XML document
- Convert XML into PYX format (based on ESIS - ISO 8879), and vice versa
XMLStarlet command line utility is written in C and uses libxml2 and libxslt from http://xmlsoft.org/.
Implementation of extensive choice of options for XMLStarlet utility was only possible because of rich feature set of libxml2 and libxslt (many thanks to the developers of those libraries for great work).
diff and patch options are not currently implemented. Other features need some work too. Please, send an email to the project administrator (see http://sourceforge.net/projects/xmlstar/) if you wish to help.
XMLStarlet is linked statically to both libxml2 and libxslt, so generally all you need to process XML documents is one executable file. To run XmlStarlet utility you can simple type xml on command line and see list of options available.
XMLStarlet is open source freeware under MIT license which allows free use and distribution for both commercial and non-commercial projects.