crontab line: 1 2 * * * [ -x /usr/sbin/rtc ] && /usr/sbin/rtc -c > /dev/null 2>&1

Posted on 2007-10-03
Last Modified: 2013-12-27
I have an old system that, if patched, we loose support on an ancient  application. So we don't patch.
I would like to move the clock for DST with a cronjob but I thought it would conflict with the line:
crontab line: 1 2 * * * [ -x /usr/sbin/rtc ] && /usr/sbin/rtc -c > /dev/null 2>&1

Even thought this is in cron I can't find "rtc" on the system. I can't find it on any of my systems. Is this missing only on my systems or do you all notice it gone too?

Would there be any reason I shouldn't rem this out since I specifically want to move the clock myself?
Question by:jjc_mn
    LVL 48

    Accepted Solution

    rtc isn't generally installed on most Solaris systems, so commenting out the cronjob will make no difference as it doesn't run anyway.

    Author Comment

    So what do the new systems use to know when to change for  DST?
    LVL 48

    Assisted Solution

    Unix/Linux systems use timezone files.

    See  /usr/share/lib/zoneinfo/src/README

    Solaris (and all other Unix flavours) produce patches whenever there are changes in DST.

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    How your wiki can always stay up-to-date

    Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
    - Increase transparency
    - Onboard new hires faster
    - Access from mobile/offline

    My previous tech tip, Installing the Solaris OS From the Flash Archive On a Tape (, discussed installing the Solaris Operating S…
    FreeBSD on EC2 FreeBSD ( is a robust Unix-like operating system that has been around for many years. FreeBSD is available on Amazon EC2 through Amazon Machine Images (AMIs) provided by FreeBSD developer and security office…
    Learn how to navigate the file tree with the shell. Use pwd to print the current working directory: Use ls to list a directory's contents: Use cd to change to a new directory: Use wildcards instead of typing out long directory names: Use ../ to move…
    This tutorial goes over how to archive and restore FreeBSD jails that are managed by ezjail.

    759 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    12 Experts available now in Live!

    Get 1:1 Help Now