use Convert::Binary:C;

$c = Convert::Binary::C->new;
binmode(S);

my $c = Convert::Binary::C->new->parse(<<ENDC);

typedef struct
{
    unsigned char type; /* length(*ver) */
    char *ver;
} R;

ENDC

$data = {type => 3,*ver => "asd",};    # it gives error
$binary = $c->pack('R', $data);
print S $binary;