Add line breaks in large XML file in one line
Perhaps that will be useful to someone:
How can I add a line break for each tag so that it is not in one line in my editor?
To do that to several files, automatically, I use XmlLint:
xmllint YOUR_FILE.xml --format
XmlLint is available in the Kubuntu/Ubuntu packages, and also can be downloaded for several operating systems in:ftp://xmlsoft.org/libxml2/