Listing 1 Create a configuration file from a template

use Date::Calc qw(:all);
# Substitutes Analog Paramters in an input Configuration Template and
# saves the new config file to disk.
sub createAnalogConfigFile {
    my ($in_filename, $out_filename, $config_substitutes) = @_[0..2];
    my $analog_config;

# Load in the template config file into a string
    open INFILE, $$in_filename or die "Cant open $$in_filename\n";
    while (<INFILE>) { $analog_config .= $_ }
    close INFILE;

# Substitute all parameters that are in the Hash
    for my $key (keys %$config_substitutes) {
        $analog_config =~ s/$key\s* \s*.*/$key $$config_substitutes{$key}/g;
    }

# Output the new config file
    open  OUTFILE, ">$$out_filename" or die "Cant open config file $$out_filename\n";
    print OUTFILE $analog_config;
    close OUTFILE;
}