XMLStarlet is a set of command line utilities (tools) 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.
The toolkit's feature set includes options to:
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
Display directories in XML format
Typical Applications: command line and shell XML processing