Calling exec() on php

Question

I can't see why exec() doesn't run on RaspberryPi but it outputs 'something'. Can someone please help me?

<?php
echo exec('GPIO.Output 1 1');  
echo('something');  
?>

How do you know it doesn't work? Is GPIO.Output an actual executable? Does it work from the command line? Does the PHP user have permission to run it? Does the webserver user have permission to access the files in /proc/ that GPIO manipulating programs need to write to? — Quentin
– Quentin, Commented May 10, 2016 at 13:02

Lee · Accepted Answer · 2016-05-10 13:01:12Z

1

Remove exec from the disabled functions in your php.ini file

answered May 10, 2016 at 13:01

Lee

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Comments

Jakub Matczak · Accepted Answer · 2016-05-10 13:03:01Z

0

exec() returns only last line of executed command's output. Use shell_exec() instead.

Alternatively you can make use of seconde exec() argument which like:

$output = array();
exec('GPIO.Output 1 1', $output);  // $output is passed by reference

Now $output contains command's output with every line as a separate array element

answered May 10, 2016 at 13:03

Jakub Matczak

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Alex Alex · Accepted Answer · 2016-05-17 12:36:50Z

0

Thank you all for your help. I used the system() function insted, and it worked. Here is the code:

`

$last_line = system('/var/www/pornire_bec.cgi', $retval);

echo ' Last Line: ' . $last_line . ' Return Value: ' . $retval; ?>`

answered May 17, 2016 at 12:36

Alex Alex

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