From: Francis Hwang <sera@...>
Date: 2004-11-12T03:03:17+09:00
Subject: Re: Writing a looping, low-configuration script in Ruby

Cool! Funny that stuff isn't in the man page. Thanks much.

On Nov 11, 2004, at 9:09 AM, Florian Frank wrote:

> On 2004-11-11 22:44:51 +0900, Francis Hwang wrote:
>> So then I was thinking: Can I have a config that automatically edits
>> the crontab? Has anybody used Ruby to programmatically edit a crontab?
>> I suppose the brute force way to do it is to call "crontab -e" and
>> send the various keystrokes to stdin, but I wonder if anybody knows of
>> a less duct-tapey way.
>
> You can install a new crontab with
> $ crontab filename
> or
> $ crontab -
> for stdin input.
>
> You can output the current crontab of $USER with
> $ crontab -l > filename
>
> Of course you can do this in a ruby script, too. In this case you 
> should
> perhaps use a lock file.
>
> If you only want to run a script every 30 minutes with cron, you
> can add a line like
> */30 * * * *    /path/to/script.rb
> to your crontab. This is actually one of the main reasons to install
> something like cron.
>
> -- 
> Florian Frank
>