SysTim        int(8)  deci-microseconds since midnight on 17-Nov-1858 AEST
Record_No     int(2)  = # of 20-secs since midnight + 1
WndSpdMax     int(2)  km/h
WndSpdAvg     int(2)  km/h
WindDir       int(2)  degrees [0..540]
AirPress      int(2)  millibars (hectopascals)
RainBuckets   int(2)  tips in the preceeding 20 seconds - 1 tip = 0.2mm
RelHumid      int(2)  %
OutTemp       int(2)  degrees-celsius
InTemp        int(2)    "
MaserTemp     int(2)    "
CbnTemp       int(2)    "
ExtrTemp      int(2)    "

##</code><code>##

#!/usr/local/gnu/bin/perl

$template="i8 i2 i2 i2 i2 i2 i2 i2 i2 i2 i2 i2 i2";
$recordsize=length(pack($template, ( )));

open(FILE,"$ARGV[0]") or die "unable to open file: $!"; 

while(read(FILE,$record,$recordsize)) {
  @fields = unpack($template,$record);
  print $fields[0], "\n";
}

close(FILE);

exit 0;