Trouble Setting Up Ad-hoc Network From Terminal - c

Question

I'm trying to connect to a server I'm running in C on a computer on a wireless ad-hoc network. The problem is when I'm to connect from another computer on the network using telnet it doesn't work. I can ping the IP address (192.168.0.1) but using:
telnet 192.168.0.1 8889
results in the error "Connection Refused" (The server is listening on port 8889 which I've verified).
I've investigated further and found that setting up my ad-hoc network using network manager solves this problem. Currently I'm setting up my ad-hoc network via terminal and I would like to keep it this way. The ad-hoc network is being setup with the following commands:
sudo service network-manager stop
sudo iwconfig wlan0 mode ad-hoc essid 'rgd' channel AUTO key OFF
Where wlan0 is my wireless device.
I'm not sure why this error is occurring. Can anybody help me with this?
Edit: #Huygens netstat -tlpen displays the following
Proto Recv-Q Send-Q Local Address Foreign Address State User Inode PID/Program name
tcp 0 0 0.0.0.0:48727 0.0.0.0:* LISTEN 1000 302920 13098/socket
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 0 273220 933/cupsd
tcp 0 0 0.0.0.0:54880 0.0.0.0:* LISTEN 1000 304089 13148/socket
tcp 0 0 127.0.1.1:53 0.0.0.0:* LISTEN 0 12886 1606/dnsmasq
tcp6 0 0 ::1:631 :::* LISTEN 0 273219 933/cupsd
tcp6 0 0 ::1:54822 :::* LISTEN 1000 46736 3297/java
I don't see my server here for some reason :(
I've added the server code I'm running here for further reference:
#include<stdio.h>
#include<string.h> //strlen
#include<sys/socket.h>
#include<arpa/inet.h> //inet_addr
#include<unistd.h> //write
int main(int argc , char *argv[])
{
int socket_desc , new_socket , c;
struct sockaddr_in server , client;
char *message;
//Create socket
socket_desc = socket(AF_INET , SOCK_STREAM , 0);
if (socket_desc == -1)
{
printf("Could not create socket");
}
//Prepare the sockaddr_in structure
server.sin_family = AF_INET;
server.sin_addr.s_addr = INADDR_ANY;
server.sin_port = htons( 8889 );
//Bind
if( bind(socket_desc,(struct sockaddr *)&server , sizeof(server)) < 0)
{
puts("bind failed");
return 1;
}
puts("bind done");
//Listen
listen(socket_desc , 3);
//Accept and incoming connection
puts("Waiting for incoming connections...");
c = sizeof(struct sockaddr_in);
new_socket = accept(socket_desc, (struct sockaddr *)&client, (socklen_t*)&c);
if (new_socket<0)
{
perror("accept failed");
return 1;
}
puts("Connection accepted");
//Reply to the client
message = "Hello Client , I have received your connection. But I have to go now, bye\n";
write(new_socket , message , strlen(message));
return 0;
}

Answer 1

You have to do things in the proper order I think.
First you should set-up your network interfaces. Once done, you should check that you can ping your network interfaces and that if you have a firewall that it would allow incoming connection on port 8889. To see of you have a firewall activated: iptables -L if there are any rule, then you have a firewall. In addition, make sure that each network interface has the expected IP address: ifconfig.
For testing purpose and if you are on a safe network, you can temporarily disable the firewall: iptables -F (precede it by sudo if you require super user privilege).
Then, you can start your server. Check that it is up and running (via ps wux) and check that it is in listening mode via netstat -tlpen.
Now try to telnet to it via telnet 192.168.0.1 8889.
PS: Of course your ad-hoc network should be on a different subnet than your local network. So if you are using both your ethernet (cable) network and an ad-hoc wifi network, each should be on a different subnet: e.g. 192.168.0.1/24 and 192.168.1.1/24.