How would I get a cron job to run every 30 minutes?

Question

I\'m looking to add a crontab entry to execute a script every 30 minutes, on the hour and 30 minutes past the hour or something close. I have the following, but

Answer 1

If your cron job is running on Mac OS X only, you may want to use launchd instead.

From Scheduling Timed Jobs (official Apple docs):

Note: Although it is still supported, cron is not a recommended solution. It has been deprecated in favor of launchd.

You can find additional information (such as the launchd Wikipedia page) with a simple web search.