SUMMARY
Starting in 2027, dates on files on UDF file systems generated by genisoimage will have incorrect time stamps. They will be set back by 16 hours. I know, this is not the fault of k3b but genisoimage, but I am reporting it here to "ring the alarm bells".

By the way, the iso9660 implementation of genisoimage is affected by the famous Y2038 bug. January 2038 will be a painful month in the world of computing, because nothing 32-bit is future-proof.

UDF and iso9660 technically have date ranges that end with the year 9999. Therefore, the date and time should not be computed by calculating seconds from an epoch. UDF and iso9660 have no epoch. They have separate fields for years, months, ..., subseconds. By the way, genisoimage does not record subseconds, but that is a topic for a different bug ticket. It is not as urgent as this.

STEPS TO REPRODUCE, OBSERVED RESULT

~~~~
# cd /tmp
# touch -m -d 2027-01-01 test2027.txt
# touch -m -d 2028-01-01 test2028.txt
# genisoimage -udf -o tmp.img test202*
I: -input-charset not specified, using utf-8 (detected in locale settings)
Total translation table size: 0
Total rockridge attributes bytes: 0
Total directory bytes: 0
Path table size(bytes): 10
Max brk space used 0
419 extents written (0 MB)
# mkdir udftest
# mount tmp.img udftest
# ls --full-time  udftest
total 0
-r--r--r-- 1 root root 0 2027-01-01 00:00:00.000000000 +0100 test2027.txt
-r--r--r-- 1 root root 0 2027-12-31 08:00:00.000000000 +0100 test2028.txt
~~~~

EXPECTED RESULT

~~~~
# ls --full-time  udftest
total 0
-r--r--r-- 1 root root 0 2027-01-01 00:00:00.000000000 +0100 test2027.txt
-r--r--r-- 1 root root 0 2028-01-01 00:00:00.000000000 +0100 test2028.txt
~~~~

SOFTWARE/OS VERSIONS
Linux Mint 21
K3b 21.12.3
genisoimage 1.1.11 (Linux)

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