exec() open application for local user

[m3bik]

I'm working on a light use/kiosk system. I have apache2 and php5 installed on Ubuntu 10.04 and I have the browser open the localhost web page by default. I would like to include a link on this page to open oowriter (open office writer) for the end user on the machine.

 

I've tried

 

exec('oowriter');

 

with no luck. I've also tried setting the DISPLAY value before the command like

 

exec('DISPLAY=:0 oowriter');

 

with no success. I don't mind have the www-data user in the sudoers file if I have to sudo the command or something, but is this possible to do?? I'm not having any luck at all!

[trq]

You might need to add the www-data user to the video group.

 

What errors are you getting exactly?

[m3bik]

Well I've verified that the error reporting is turned on, but I don't actually get any errors when loading the webpage..

 

I have tried adding the www-data to the video group with no luck. I've also tried adding the www-data user to the user group running on the desktop, but still nothing.

 

I do have success running "php ./myfile.php" in the command line. It does open the application on the local user's screen.. but for some reason when I access the page on the web, I get nothing

[kicken]

You could try:

 

putenv('DISPLAY=:0');
exec('oowriter');

 

Also, the server may be using a PATH which does not include where oowriter is at.  Try using an absolute path to the file.

 

[m3bik]

Thanks kicken! That did the trick!

 

I did have to add the www-data user to the sudoers file because it wasn't working without "sudo" but here's my end result:

 

putenv('DISPLAY=:0');
exec('sudo oowriter');

 

[trq]

I wouldn't be running oowritter as root. You've just opened a massive security hole. There is nothing stoping anyone editing any file on the system as root.

 

You need to find out exactly what group www-data needs to be in and add them to it.

[m3bik]

Thanks for pointing that out, thorpe. I will look into it, but as a proof of concept sort of deal, I got it working.. That makes me happy.

[m3bik]

As a reference here, I eventually changed the user that apache runs under to the user name in question.. and it works without sudo now.

[trq]

Which user did you change it to? Not root I hope.