Xmldego provides XML parsing and/or transformation by binding callbacks to XML parsing events in the context of an XML element. While SAX, for example, calls your callbacks on every start tag, Xmldego will do so only for the child axis path you request. Xmldego is particularly useful when only smaller bits of a much larger XML file need to be processed, because only interest in the relevant bits need to be coded. In contrast to a DOM parser, much larger XML files can be processed, because the whole file is not loaded into memory.
csvgrep is a commandline program which enables users to execute searches on text-delimited files using a rudimentary query language. Its query language is bound to simplicity and expressivity, to be easily comprehensible. It aims at replacing both grep and awk when you are challenged to retrieve information from a text-delimited file based on the content of a specific field (or column). You can get what you want using the semantic already in the file’s underlying structure.