zt

#!/usr/bin/gawk -f
BEGIN {
  zfslist=0;
}
{  
   suffix = "";
   if ( NF > 1 )
      { 
        n = split($0, a, " ", b);
        /* Cheap check if it's a normal zfs list command */
        if (a[0] == "NAME")
          zfslist=1;
        if (zfslist)
          infix = "                  ";
        else
          infix = "";
        /* number has to be 10 digits */
        tmp = match(a[1], /.*home.*[0-9a-fA-F]+@([0-9]{10}($|\s))/, ary);
        if (tmp)
          { 
            dte = ary[1];
            cmd = "date -d @" dte " +%Y%m%d_%H%M%S";
            cmd | getline result;
            a[1] = a[1] " - " result;
            close(cmd);
          }
        else
          { /* see if I can find something that looks like a date */
            tmp = match($0, /(^|\s)([0-9]{10})($|\s)/, ary);
            if (tmp)
              { 
                dte = ary[2];
                cmd = "date -d @" dte " +%Y%m%d_%H%M%S";
                cmd | getline result;
                suffix = " - " result; /* print at the end because we don't know where it is */
                close(cmd);
              }
            else
              a[1] = a[1] infix;
          }

        line=b[0];
        for ( i = 1 ; i <= n; i++)
            line=(line a[i] b[i])
        print line suffix;
      }
    else
      print $0;
}
/* END { print "done"; } */