Maintenance of btmp

• When we get to the second file, test each user for presence in the array “vu”

  
  NR > FNR && $1 in vu
    {
  # keep a subscripted array
    for (i=5; i>0; i--)
      data[$1,i]=data[$1,i-1]
    data [$1,0]=$0
    }