sscanf vs istringstream

What is the istringstream equivalent of sscanf and checking if 4 fields have been read in?

Code:

---

if (sscanf(s, "%d %s %c %s", &id, variable, &type, value) == 4)

---

versus

Code:

---

std::istringstream mystream(s);

// scan 4 fields
mystream >> id;
mystream >> variable;
mystream >> type;
mystream >> value;

if (mystream ????)

---

If a stringstream fails to read something, it sets a bad bid, so just check the stream, ie:
if (mystream) // OK
if (!mystream) // Not OK

if (mystream >> id) // OK
if (!(mystream >> id)) // Not OK