I understand that UDF is completely different from ISO9660 and I don't expect fine-level editable UDF support to be implemented in xorriso. Perhaps some different program could be made for this, but it would be good to have DAO (disc-at-once) UDF support at least.
genisoimage already has it, but it is unmaintained since - what was it - 2010? And it is showing: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=990468;msg=7 (the 2027 date bug) The good things about UDF are longer file name limits on Windows and longer volume label limits. Though from my testing, ISO9660 has a lower file system overhead, so it would be preferrable for many small files (tens of thousands). UDF 1.02 is enough for DAO purposes. Anything after that is mainly for stuff like packet writing / live file system.
