static extern int swapcontext(ucontext_t* __oucp, ucontext_t* __ucp);
//extern void makecontext(IntPtr* __ucp, RunDelegate __func, int __argc, params IntPtr __rest); static extern void makecontext(ucontext_t* __ucp, RunDelegate __func, int __argc);
static extern int setcontext(ucontext_t* __ucp);