GDB Analysis of the ROPE machine

I am working on the ROPE machine. I have set up PEDA to be run with my GDB. Currently I am following IppSec’s tutorial. At 00:12:35 of his tutorial, his GDB shows the arguments that are passed to the accept() system call. I tried to use the “dumpargs” command but it didn’t show the arguments.

Do I have to change something in the configuration file to see the arguments that are being passed to a system call at a particular break point or what.