namespace libapp
{
struct S0;
struct S1;
struct S2;
struct S3;
S0*
create_s0();
void
destroy(S0*);
S1*
create_s1();
destroy(S1*);
int
fun0(S0&);
fun1(S1*);
fun2(S2*);
fun3(S3*);
} // end namespace libapp