What does it mean to give a process CAP_SYS_RAWIO in linux?

Question

What does it mean to give a process CAP_SYS_RAWIO in linux? How do I do that? (Specifically to give pyUsb access to devices. This is related to this pyusb question)

Answer 1

From the capabilities(7) man page:

  CAP_SYS_RAWIO
          Perform I/O port  operations  (iopl(2)  and  ioperm(2));  access
          /proc/kcore.

Capabilities are set on an executable with setcap(8).