Hi,
It means "setuid". That is, the program is run with the privileges of the owner of the program. In our case, that means "run pd as root". And so it can do anything it wants to your system.
Generally, root has no limits on ressources (cpu, memory, priority) compared to other users.
The setuid bit is more often used for programs like su or sudo for privilege escalation, or X (the display server) to be able to access the video card. But you can also use it as a quick hack to get unlimited credits :).
Pierre Massat wrote:
I'm not very familiat with chmod codes. What does 4755 mean ?
One slight tweak: if you type "sudo chmod 4755 /usr/bin/pd" you will probably be able to use the mouse clicklessly (at some expense to security!)