Gtk-WARNING **: cannot open display: [for www-data user]

[roger_girardin]

hi all
i want to run an external prog by a web interface (user : www-data)

the prob is when i do by a console :
su www-data
vmware

the prog is workin fine

if i sent this command by a web interface, it doesn't launch
if i edit /var/log/apache/error.log, i can see " Gtk-WARNING **: cannot open display: "

knoppix 3.4 kernel 2.4
it worked fine on a previous knoppix install but i have messed up with permission and i had to reinstall
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i have changed the user www-data privileges to users then to root, but nothing
i have changed the apache user to my current user but nothing
i have create a symlink from .xauthority user to www but nothing
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have you any ideas ?

[mzilikazi]

Looks like root is not allowed to use the X server. As user issue:
xhost local:

Then I would do:

apt-get install sux

[roger_girardin]

thanks for the reply dude

so i have installed sux

but the prog to be launch is not from a console so it doesn't display any prompt asking for pass

i have installed sarge testing and i will try to figure x better