hi all
i am new in unix programming i want some help from this forum, i want to know how to get user name of other machine in local network from its ip address or suggest any books for networking programming on unix

sachin

User name? Or do you mean hostname? The usernames on a system usually won't have anything to to with the IP address of that system.

thank for this quick reply

so please tell about how to get host name from ip address, if you have any idea about web link or book about this problem please forward me

There are a few ways.
Not using C: Use actual unix commands instead of C library functions. Two of the methods are using grep on the /etc/hosts file, and using nslookup/dig. In a C program, you can use these via popen and fread/fgets/fscanf on the file pointer returned by popen.
Using C: Take a look at the man page of gethostbyname/gethostbyaddr.

http://www.amazon.com/Unix-Network-P...e=UTF8&s=books

Unix Network Programming, Vol. 1: The Sockets Networking API, Third Edition.
ISBN: 0131411551

This book is absolutely priceless when learning anything about network comm. in Unix.

another way if you are not using dns or /etc/hosts is:
ssh <ip> "hostname" but you'll need a userpasswort on the machine

or telnet or rlogin or whatever

Or just use ping..

# ping -s 192.168.1.1 2 2
PING 192.168.1.1: 2 data bytes
10 bytes from mercury (192.168.1.1): icmp_seq=0.
10 bytes from mercury (192.168.1.1): icmp_seq=1.

----192.168.1.1 PING Statistics----
2 packets transmitted, 2 packets received, 0% packet loss
#

This shows that IP 192.168.1.1 is mercury