Linux time and date

Convert epoch to date

date -d @'1475584168'

traditional syslog time

date -d @'1475584168' +'%b %e %T'

Whole (traditinal) syslog header

echo "$(date -d @'1475584168' +'%b %e %T') $(hostname) programname:"

Fix date format

i.e. 2021/01/20 -» 2021-01-20

sed -i -E 's,([0-9]{4})/([0-9]{2})/([0-9]{2}),\1-\2-\3,g' journals/*

libfaketime

• GitHub
• FR: freeze Browser time
• Beware: Wall clock continues running from fake starting point

Examples:

LD_PRELOAD=/usr/lib/faketime/libfaketime.so.1 FAKETIME="-15d" chromium
FAKETIME_DONT_RESET=1 faketime '2024-03-01 00:00:00' node generate-pdf.js

libfaketime in container

$ docker run --rm -it -e FAKETIME="2023-12-31 23:59:00" docker.io/skto/faketime:v90 date
Wed Nov 29 10:03:08 UTC 2023