#!/usr/bin/perl -w
#
# temptrax.extract
#
# simple perl script to extract TempTrax sensor output
# varhus, 20020917

use Getopt::Std;

my $temptrax_output;
my($mon, $mday, $year, $hour, $min) = (localtime(time))[4,3,5,2,1];


use vars qw($opt_l);

my $USAGE     = "usage: temptrax.extract [-l logfile]\n";

# process command-line arguments
getopts('l:') or die "$USAGE";


my $SERDEV = "/dev/ttyS0";

open(SERIAL, "+< $SERDEV") or die "couldn't open $SERDEV";
my($rin) = '';
vec($rin, fileno(SERIAL), 1) = 1;

for (my $i = 0; $i <= 1; $i++) {
  print SERIAL "\n";
  last if select($rin, undef, undef, 2);
}

my $read;
for (my $len = 0; $len < 22; $len += $read) {
  my $buf;
  $read = sysread(SERIAL, $buf, 22 - $len);
  $temptrax_output .= $buf;
}

close(SERIAL);

$temptrax_output =~ m/(-{0,1}\d+\.\d)\W/gs;
my $probe1 = $1;
$temptrax_output =~ m/(-{0,1}\d+\.\d)\W/gs;
my $probe2 = $1;

if (defined $opt_l) {
    # my($datafile) = sprintf("%s/%s-%02s-%02s", "/var/spool/temptrax/data",
    #                    $year + 1900, $mon + 1, $mday);
    open(DATA, ">> $opt_l") or die "couldn't open $opt_l";
    printf DATA "%02s%02s %s %s\n", $hour, $min, $probe1, $probe2;
    close(DATA);
} else {
    printf "%02s%02s %s %s\n", $hour, $min, $probe1, $probe2;
}

exit(0);