Getting IP address in C

hraja's Avatar, Join Date: Apr 2010
Light Poster
Hi,

I wish to get the system IP address in my C program. Unfortunately, when I tried the following code, I kept getting 127.0.1.1 and not the actual IP address of my system.

struct sockaddr_in server_addr;
struct hostent *host;
char hostname[256];

gethostname(hostname, sizeof(hostname));
host = gethostbyname(hostname);
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(5000);
server_addr.sin_addr = *((struct in_addr *)host->h_addr);
printf("IP address: %s\n", inet_ntoa(server_addr.sin_addr));


Thanks!
0
shabbir's Avatar, Join Date: Jul 2004
Go4Expert Founder
What is the string in your hostname?
0
shaju1981's Avatar, Join Date: Jan 2010
Newbie Member
Quote:
Originally Posted by hraja View Post
Hi,

I wish to get the system IP address in my C program. Unfortunately, when I tried the following code, I kept getting 127.0.1.1 and not the actual IP address of my system.

struct sockaddr_in server_addr;
struct hostent *host;
char hostname[256];

gethostname(hostname, sizeof(hostname));
host = gethostbyname(hostname);
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(5000);
server_addr.sin_addr = *((struct in_addr *)host->h_addr);
printf("IP address: %s\n", inet_ntoa(server_addr.sin_addr));


Thanks!
Perform WSAstartup before calling any socket function

WORD wVersionRequested; WSADATA wsaData; int err;/* Use the MAKEWORD(lowbyte, highbyte) macro declared in Windef.h */ wVersionRequested = MAKEWORD(2, 2); err = WSAStartup(wVersionRequested, &wsaData);

Now it may work .... :-)