This has probably been done a million times, but whatever. I crafted it for use in Parrot's Configure.pl script (see my home node). The function takes one parameter--a filename with dots replaced by underscores--and reads in $filename.in. It then does all the substitutions necessary, s/_/./g's the filename, and writes the result out.
sub buildfile {
    my($filename)=shift;

    local $/;
    open(IN, "<$filename.in") or die "Can't open $filename.in: $!";
    my $text=<IN>;
    close(IN) or die "Can't close $filename.in: $!";

    $text =~ s/\$\{(\w+)\}/$c{$1}/g;
    $filename =~ s/_/./;    #config_h => config.h

    open(OUT, ">$filename") or die "Can't open $filename: $!";
    print OUT $text;
    close(OUT) or die "Can't close $filename: $!";
}

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In reply to Simple templater by BrentDax

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