WiFi - Arduino Reference ; connect() returns true or false
Rubbish.
class WiFiClient : public Client {
public:
WiFiClient();
WiFiClient(uint8_t sock);
uint8_t status();
virtual int connect(IPAddress ip, uint16_t port);
virtual int connect(const char *host, uint16_t port);
connect() returns an int. The specific value just might provide a clue.