Topics: AIX, System Admin

Calculating with UNIX timestamps

Starting with AIX 5.3, you can use the following command to get the number of seconds since the UNIX EPOCH (January 1st, 1970):

# date +"%s"
On older AIX versions, or other UNIX operating systems, you may want to use the following command to get the same answer:
# perl -MPOSIX -le 'print time'
Getting this UNIX timestamp can be very useful when doing calculations with time stamps. If you need to convert a UNIX timestamp back to something readable:
now=`perl -MPOSIX -le 'print time'`
# 3 months ago =
# 30 days * 3 months * 24 hours * 60 minutes * 60 seconds =
# 7776000 seconds.
let threemonthsago="${now}-7776000"
perl -MPOSIX -le "print scalar(localtime($threemonthsago))"




If you found this useful, here's more on the same topic(s) in our blog:


UNIX Health Check delivers software to scan Linux and AIX systems for potential issues. Run our software on your system, and receive a report in just a few minutes. UNIX Health Check is an automated check list. It will report on perfomance, capacity, stability and security issues. It will alert on configurations that can be improved per best practices, or items that should be improved per audit guidelines. A report will be generated in the format you wish, and the report includes the issues discovered and information on how to solve the issues as well.

Interested in learning more?