[SOLVED] reading gpio with php exec failing on rc.local raspberry

Issue

I have an infinite loop in a PHP script that read my gpio (with wiringPI) in this manner

$newstatus = trim(exec("gpio read ".$gpioline[$i]));

and this line in rc.local to start on boot

php /root/CheckGPIO.php &

the issue is that when the script is started automatically on boot $newstatus is an empty string variable instead executing php /root/CheckGPIO.php & from the terminal once i have terminal access, all is working good and i get the gpio value in $newstatus

what can cause the issue?

PS. looking at output exec("whoami") script is ever executed as root

Solution

The issue was PATH not defined when the script called from rc.local

Answered By - FrancYescO