bash$ sudo nmap -O ace

Starting nmap V. 2.12 by Fyodor (fyodor@dhp.com, www.insecure.org/nmap/)
Interesting ports on ace (192.168.1.10):
Port    State       Protocol  Service
80      open        tcp        http            

TCP Sequence Prediction: Class=constant sequence number (!)
                         Difficulty=0 (Trivial joke)
No OS matches for host (see http://www.insecure.org/cgi-bin/nmap-submit.cgi).
TCP/IP fingerprint:
TSeq(Class=C%Val=0)
T1(Resp=Y%DF=Y%W=C8%ACK=S++%Flags=BAS%Ops=)
T2(Resp=Y%DF=Y%W=C8%ACK=O%Flags=A%Ops=)
T3(Resp=Y%DF=Y%W=C8%ACK=O%Flags=UASF%Ops=)
T4(Resp=Y%DF=Y%W=C8%ACK=O%Flags=A%Ops=)
T5(Resp=Y%DF=Y%W=C8%ACK=S++%Flags=AR%Ops=)
T6(Resp=Y%DF=Y%W=C8%ACK=O%Flags=AR%Ops=)
T7(Resp=Y%DF=Y%W=C8%ACK=O%Flags=UARF%Ops=)
PU(Resp=N)


Nmap run completed -- 1 IP address (1 host up) scanned in 59 seconds