exec() php function returns an unwanted empty file

Question

I am running a simple PHP script which calls a Python script using exec() in PHP to activate GPIO pins on a Raspberry Pi to turn (or keep) a light on or off. The script is called by cron every 5 minutes. It works fine, but writes an empty file with the same name as the script each time the script is run. The key part of the script is:

$command = "sudo python lights.py 0"; $result = shell_exec($command);

I have tried it like this:

$command = "sudo python lights.py 1"; $result = exec($command); 

And I have tried it with or without echo $result . In all cases I get the empty file written to the /home/pi directory. The script is run in /var/www/working directory .
The cron script is

*/5 * * * * /usr/bin/wget [lan_address]/working/lampRoutine.php >> dev/null 2>&1

Can anyone help?

Answer 1

I have found a solution. The problem was with the cron script. If I add the argument '-O' to the wget command I get no empty file.

wget -O - https://[lanAddress]/path/To/Script >> /dev/null 2>&1