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Tag: unix

do you know crontab?

simple brainteaser. take no more than 30 seconds to think about it:

using standard cron installed on your unix system, how often would this command be run:

*/57 * * * * command

? if you choose to answer in comments, please supply version of cron that your system is using.

Posted on 2008-04-16|Tags brainteaser, cron, linux, unix|5 Comments on do you know crontab?

unix crontab and longest interval

simple brain teaser:

given standard unix crontab what is the longest possible interval between calls to the same program?

for example:

15 */2 * * * /bin/echo x

has interval 2 hours.

what is the longest possible? and how to make it?

Posted on 2008-03-212016-04-04|Tags brain teaser, cron, unix|10 Comments on unix crontab and longest interval

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