Multisite with cron-curl.sh

Here I detail my battle and ultimate victory in setting up cronjobs to run for live multiple drupal
websites. I found it very arduous to get cronjobs to work on my webhost. Also, drupal guide pages
and support pages were much lacking. Even the scripts that come with drupal were not complete
enough as it seems a 'user-agent' must be specified for the script to work.

Errors returned from cronjob run attempts:

• /bin/sh^M: bad interpreter: No such file or directory - click the preceding link for help

The gist of the problem and solution that worked for that was inappropriate file encoding.
Windows will make the encoding of the .sh files unusable for the Unix which handles the files if
the file is edited and saved on your local Windows computer. And you can't do without changing
example.com in the drupal scripts! You can convert to correct Unix form with the dos2unix online tool.

Tip: a great helper for checking for the proper file format is to 'view' the file in cPanel and look for the
detected type right at the top of the page. You want to see "Bourne shell script text executable "
for your cron-curl.sh file.

• permission denied

You can use filemanager in your hosts cPanel to check and set permissions with a right click on
a file or directory. Files and directories must have sufficient permissions. In this case the scripts
directory, the cron-curl.sh file, and perhaps the cron.php file needed to be reset from 644 to 755.

Here is the curl script that worked:

  curl --silent --compressed -A "Mozilla/5.0" http://works1.com/cron.php
  curl --silent --compressed -A "Mozilla/5.0" http://works2.com/cron.php
 
 

Here is the cron line that runs it correctly once every day at midnight:

  0 0  * * * /home/webhostaccountname/public_html/scripts/cron-curl.sh

Some good references:

• You may want to go to curl.haxx.se to look for official curl options.
• Good general starter info on cron is at wikipedia-Cron