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Snow Leopard and crontab

It seems that somewhere along the line the ability to list and edit your user crontab went away, maybe they are wanting to migrate people across to "launchd" and "launchctl" as the preferred way of doing things. One of the things I still like about Apple is the fact that under the hood it's still  rock solid Unix, and that most of the time, if it works on Ubuntu it works on OS X too, sometimes it may look a little different but in the end you can still bask in some command line warmness to be able to achieve what you want.

So, if the commands crontab -l and crontab -e appear not to work anymore, how do you get the same result? For the record, running uname -a on my iMac gives me:

Darwin Macintosh.local 10.8.0 Darwin Kernel Version 10.8.0: Tue Jun  7 16:33:36 PDT 2011; root:xnu-1504.15.3~1/RELEASE_I386 i386

Your mileage may vary if its radically different than that... a long time back I wrote a PHP class wrapper around the cron system so that it would allow an application to programmatically add, edit and delete cron jobs without upsetting what was already in place. How did I do this from PHP? Simple. There is another way to use the crontab command that a lot of people know but not a lot of people know people who know how to do it, so here it is...

Dumping your current crontab:
crontab -l ~/tmp/mycrontab

Once there, you can edit it to your hearts content until it's how you want it and then

Updating your current crontab:
crontab ~/tmp/mycrontab

All my PHP code did was wrap that in calls to exec() and all my stuff I put at the bottom of the file between two "special" markers do I'd know where was safe to read and write, a reminder of my days with Microsoft Frustration Classes waaaaaayyyyyy back in the 80's when VC++/MFC was "hot". LMFAO

So, there you are. Voila. Job done. All over. Simple once you know how. Hope that helps somebody else save a bit of head-scratching.

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