Test if an IP is being used in an internal network without using nmap
Solution 1:
You can use ping:
ping 192.168.1.9
Most of the machines will reply, but some wont. If it's in the same local network, you can check the arp (after a no-reply):
arp -n | grep 192.168.1.9
(-n shows numeric IP addresses - does not try to resolve hostnames)
Solution 2:
I assume there is some reason why ping 192.168.1.9 is unacceptable? If you're looking for a device that might be firewalled, but is on the local broadcst network, ping 192.168.1.9 followed by arp -a -n|grep 192.168.1.9 can be a more reliable way of finding an otherwise-silent host.