xds2sad
It reads XDS_ASCII.HKL and outputs a file xds.sad that contains direction cosines and can be read by the Bruker program SADABS. (Summary from the program web page.)
The official web page: https://wiki.uni-konstanz.de/xds/index.php/Xds2sad.
Typical usage
$ module add xds2sad
$ xds2sad args