How to get host name from host ip using C

nagendrar · 12-01-2009, 06:00 AM

I know host ip of system in domain.But I don't know the hostname of that system.

Please give small example to get host name from host IP using C.

ThanQ,
Nagendra Rednam

JohnGraham · 12-01-2009, 07:31 AM

Look up the gethosthostbyaddr() function - you can use the Linux manpages or search online.

John G

nagendrar · 12-01-2009, 10:18 PM

I got hostname following way

int main(){
hostent * sHostent = 0;
char hostname[1024];

unsigned long addr = inet_addr("<IP>");
if (addr != INADDR_NONE)
sHostent = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET);

if (sHostent) //Host address is a name
{
sprintf(hostname, "%s", sHostent->h_name);
printf("===%s",hostname);
}
}