Convert epoch seconds to datetime

Some of the logs I debug often contain the timestamp in the form of epoch seconds, so I frequently had to convert them into readable datetime format. Noting this down for a quick reference.

macOS

# % date -r <seconds>
~ % date -r 1220355645
Tue Sep  2 07:40:45 EDT 2008

Linux coreutils

# date -d @<seconds>
$ date -d @1120355645
Sat Jul  2 21:54:05 EDT 2005

coreutils date conversion specifiers

Display current time in epoch seconds

(common to both macOS and coreutils)

~$ date +%s
1620355706