Describe the "port" file.
 [rsc] --rw-rw-r-- M 249245 glenda sys 6960 Sep 17 11:37 sys/man/3/usb
	/n/sourcesdump/2005/0917/plan9/sys/man/3/usb:201,206 - 
	/n/sourcesdump/2005/0918/plan9/sys/man/3/usb:201,209
	  .SH FILES
	  .TF "#U/usb n /*/status"
	  .TP
	+ .BI #U/usb n /port
	+ USB port status file; for each port, space separated: port number, hexadecimal port status, port status string
	+ .TP
	  .BI #U/usb n /*/status
	  USB device status file; class/subclass/proto, vendor-id and product-id are found in line one
	  .TP