Examples:
date +%s date -d @1640290674 date +%s -d"Jan 1, 1980 00:00:01" w32tm.exe /ntte 131001091660000000
date +%s
date -d @1640290674
date +%s -d"Jan 1, 1980 00:00:01"
w32tm.exe /ntte 131001091660000000