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The date command can display the time in Unix epoch format (seconds since 1970-01-01 0:00:00) like this:
date
date +%s
But how do I convert a timestamp in epoch format back to a human-readable date/time?
The date command can do that as well. Prefix the epoch timestamp with @ and pass that to the command as the date string (via the parameter --date/-d):
@
--date
-d
ts="$(date +%s)" date --date @"$ts"
