Since these members are used to hold members defined now as u_quad_t
in struct if_data, u_long is quite not enough actually.
Without this, one night ttcp easily makes netstat to produce wrong output
like this:
enami@annex-2f-floor-244% netstat -ibw 1 -I tlp0
tlp0 in tlp0 out total in total out
bytes bytes bytes bytes
176333740607 176914940420 240082591 821282404
176093659136 176093659136 0 0
176093659136 176093659136 0 0
7e18584b57