#!perl.exe -w     replace for real OSs     
use strict;
use warnings;

my $debug = 1;

sub get_value   # used in substitution
{
    my ($ref_values, $key) = @_;
    print "    look for $key ?\n"   if $debug;

    my $result = ( exists $ref_values->{$key} )   # if exists ...
	         ? $ref_values->{$key}            # return Value 
                 : "*ERR*"                        # else return *ERR* 
}	

sub generate_file
{
   my ($templ_file, $ref_inivars, $target_file) = @_;
   
   open IN,  "<$templ_file"    or return -1;
   open OUT, ">$target_file"   or return -2;
   
   while ( my $line = <IN> )
   {
       $line=~s/\$\((\w+)\)/&get_value($ref_inivars,$1)/ge;
       print OUT $line;
   }
   return 0;
}

#------------------
# Use the Code
generate_file ( "./template/inifile.ini",
                { %ENV,          # just to demonstrate
		  'RUNTIME'  =>  "~/prod/test/v1.2/bin",
                  'VERSION'  =>  "v1.2",
                  'ENVIRONMENT' => "test"
                  'DATABASE' =>  "L63DTST",
		},
                "result.ini" );