#! perl -slw
use strict;
use Data::Dump qw[ pp ];

my %tmpls = (
    '1,2,3,4' => {
        I => { 16 => 'v*', 32 => 'V*' },
        F => { 32 => 'f<*' },
        D => { 64 => 'd<*' },
    },
    '4,3,2,1' => {
        I => { 16 => 'n*', 32 => 'N*' },
        F => { 32 => 'f>*' },
        D => { 64 => 'd>*' },
    },
);

open FCS, '<:raw', 'c:\downloaded\FCSExtract-TestData\FloatData4031.fcs'
    or die $!;

sysread( FCS, my $header, 58 ) or die $!;

my( $id,
    $sText, $eText,
    $sData, $eData,
    $sAnalysis, $eAnalysis
) = unpack 'A6 x4 (A8)6', $header;

sysseek FCS, $sText, 0 or die $!;
sysread( FCS, my $text, $eText - $sText ) or die $!;
my $delim = substr $text, 0, 1, '';
my %text = split $delim, $text;

pp \%text;

sysseek FCS, $sData, 0 or die $!;
sysread( FCS, my $data, $eData - $sData ) or die $!;

my $tmpl = $tmpls{ $text{ '$BYTEORD'  } }
                 { $text{ '$DATATYPE' } }
                 { $text{ '$P1B'      } };
die 'Can\'t handle format' unless $tmpl;

my @data = unpack $tmpl, $data;

pp \@data;