exec() with Linux

[Stefano]

I have to execute vlc (Video Lan) using exec() function under Linux debian
distribution. Running vlc from a shell works perfectly, but I have a lot of
problems if it is executed with function exec:

TEST 1

<php
$command = "vlc";
exec ($command);
?>

I get an error message in apache log file:

VLC media player 0.8.6c Janus
[00000287] skins2 interface error: Cannot open display
[00000287] skins2 interface error: cannot initialize OSFactory
Error: Unable to initialize gtk, is DISPLAY set properly?

What is the DISPLAY to set ? Please consider I am a newbie in Linux.
TEST 2

Same as before but running vlc with --daemon option. Now seems that vlc
process is running and I don't get any error message in apache log file, but
it does not record any input stream.

Is there anybody that can help me ?
Thank you.
Stefano

[Darko]

On Nov 5, 6:45 pm, "Stefano" <[e-mail]:

I have to execute vlc (Video Lan) using exec() function under Linux debian
distribution. Running vlc from a shell works perfectly, but I have a lot of
problems if it is executed with function exec:

TEST 1

<php
$command = "vlc";
exec ($command);
?>

I get an error message in apache log file:

VLC media player 0.8.6c Janus
[00000287] skins2 interface error: Cannot open display
[00000287] skins2 interface error: cannot initialize OSFactory
Error: Unable to initialize gtk, is DISPLAY set properly?

What is the DISPLAY to set ? Please consider I am a newbie in Linux.

TEST 2

Same as before but running vlc with --daemon option. Now seems that vlc
process is running and I don't get any error message in apache log file, but
it does not record any input stream.

Is there anybody that can help me ?

Thank you.
Stefano

Think about executing another application in the web-environment: do
you think it would work if you tried to exec( "winword" ) (Microsoft
(R) Word)? Of course not. You can't just "run" an application from php
and have it shown in the browser window.

[Stefano]

You are probably on the right track, but it's going to be hard for anyone
to help without knowing that program. Here's an idea: From a shell window,
do "unset DISPLAY", then try to get the program to do what you want. Once
you can do that, you can try it from the web server.

It doesn't work unsetting DISPLAY.
May be using vlc is not the right way to record a video stream in php. Do
you know other ways to do that ?