base.dir uri base.dir The base directory of chunks If specified, the base.dir parameter identifies the output directory for chunks. (If not specified, the output directory is system dependent.) Starting with version 1.77 of the stylesheets, the param's value will have a trailing slash added if it does not already have one. Do not use base.dir to add a filename prefix string to chunked files. Instead, use the chunked.filename.prefix parameter.