Thanks for replies, I've found a solution.

I am using the xvfb-run command:

xvfb-run pd-extended patch.pd

Which will run the pd-extended command on a virtual display, without returning any errors.

Slidon

Hi David,

I have installed the x11vnc package am running the server with the command

x11vnc -display :0

Pure Data still gives the same no display error. What command are you using to run x11vnc?

I am trying to run my Pure Data patch on a Raspberry Pi without a screen.

It runs fine when I attach a display and launch it from the command line.

However if I use the -nogui command line argument, the patch reports:

ALSA input error (snd_pcm_open): Device or resource busy

And I am unable to run it normally without a screen plugged as it reports this error:

Application initialization failed: no display name and no $DISPLAY environment variable

Why does adding -nogui stop the program running? Otherwise what's the best workaround?

Thanks in advance, Slidon