After a while, I found that the some of the configuration files to make this project go are available from a gent named Michael Dear via a program/offering called Totalmarker. Totalmarker is a result of some perl scripts that create the cloud overlay; pull the volcano, earthquake, and storm data from the national sites; and also pulls the data from NORAD about the ephemeris for the Space Station and the Shuttle (when it up). This makes everything much easier. However, I quickly got tired of pulling the files every so often so I decided to see if I could script this somehow.It turns out that volcano data (for example) is only updated once a week, so there is not point in pulling it more often than that. Cloud data is updated about every 6 hours, so I could pull the cloud image every 6 hours. I needed something that I could schedule and windows scheduler was just too clumsy for me to figure out. So I did it the hard way, of course.The search for yet another capability led me to a new software program called nncron (lite), which acts as a cron service for windows. A cron service, if you don’t know, is something that runs in the background and checks to see if there is something it needs to do (like watching a folder for new files or emails that have been posted and then moving them to the appropriate location). I built a configuration file for nncron that schedules the various data pulls according to the frequency of their updates. (This is called a cron.tab file). Mine read like this attached file:
If you don’t speak ‘cron’, don’t worry. I didn’t either. I spent a lot of time on the website and with the documentation and figured it all out. All the lines above say is to download the appropriate configuration file (quake, cloud, etc.) at the times listed above. There isn’t much point in downloading more often, the files don’t change. So for example, the cloud file is built 4x a day. Downloading it more often than that wasn’t going to do me any good.So I loaded this up and, after a lot of testing, got it to work.
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