Thank you for all the information :)

Also, my general advice for running anything from cron is always use absolute paths

Following this advice I have used the full path so my cron entry is: 

*/2 * * * * /usr/bin/perl /home/pi/Curtains/curtains.pl

[download]
If I use /usr/bin/perl /home/pi/Curtains/curtains.pl from the command line then the script runs but it doesn't run from cron. So I have enabled logging in /etc/rsyslog.conf and I get this logged: 
Dec 14 16:12:01 eric CRON[10129]: (pi) CMD (/usr/bin/perl /home/pi/Cur
+tains/curtains.pl)
Dec 14 16:12:01 eric CRON[10128]: (CRON) info (No MTA installed, disca
+rding output)
Dec 14 16:14:01 eric CRON[10135]: (pi) CMD (/usr/bin/perl /home/pi/Cur
+tains/curtains.pl)
Dec 14 16:14:01 eric CRON[10134]: (CRON) info (No MTA installed, disca
+rding output)

[download]
That explains why I am not getting any mail! But doesn't explain to me why the script is not running from cron. I have tried chmod 777 curtains.pl and chmod 755 curtains.pl.

What else should I be looking at to try and debug this problem>

In reply to Re^3: Continuous or timed? by Bod
in thread Continuous or timed? by Bod

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