namespace libapp
{
struct S0;

struct S1;

struct S2;

struct S3;

S0*
create_s0();

void
destroy(S0*);

S1*
create_s1();

void
destroy(S1*);

int
fun0(S0&);

void
fun1(S1*);

void
fun2(S2*);

void
fun3(S3*);

} // end namespace libapp