OK, when your command output is used as input to another command, it is "piped" into the command. In the Bourne shell, the usual "pipe" is indicated by a vertical bar. For example, if you wanted to list all files in a directory containing the word "test," you could "pipe" the output of the "ls" command into the "grep" command like this:
Now, once you set that up, both commands must work together. If one fails, then the "pipe" is broken, and the shell gives you the "broken pipe" message.
In your specific case, your command syntax looks strange to me, and you don't mention what distribution you're using. (Hint: Click on "My LQ" at the top of the page and fill out the registration form. Then that information will automatically be displayed with your message in the frame at the left.) But sudo
would normally apply to only the first
command in a string of commands, and, probably, one of the later commands also needed su
to run, so it failed and "broke the pipe."