Thread: Multi Threaded Web server question

Hi there I'm currently working on a Multi Threaded webserver.

So far I have manged to set up the webserver on an infinate loop waiting for a request at the socket.
This is where it gets abit weird, Yesterday I managed to find an example of reading a html code into a buffer then sending that buffer to the a browser and it would display fine.

However I have then tried to Implement the multi thread with the CreateThread function, unfortunalty I was unable to fully understand.. but when I tried to go back to just my single threaded webserver its not working now... I have no idea why after hours of fiddling around with stuff have now decided to look for some help.

Here is my code... any help would be greatly appreciated. I have commented fairly well so that should help you understand what I'm working towards.

Code:

#include <stdio.h>
#include <stdlib.h>
#include <winsock.h>

int main() {
   int s,n;
   unsigned fd;
   struct sockaddr sin={AF_INET,{31,144,0,0,0,0,0,0,0,0,0,0,0,0}};
   WSADATA wsaData;
   char *header="HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n";
   char data[512];
   char filename[256];
   FILE *f;
   
   WSAStartup(MAKEWORD(1, 1), &wsaData);  // initialise windows sockets
   s=socket(PF_INET,SOCK_STREAM, 0);      // create a socket
   bind(s,&sin, sizeof(sin));             // bind it to port 80
   listen(s,10);                          // allow up to 10 incoming connections 
   while(1) {
      fd=accept(s,NULL,NULL);             // wait for a request 
      n=recv(fd,data,512,0);              // recieve the request using fd
      data[n]=0;                          // NUL terminate it
      sscanf(data,"GET /%s ",filename);   // get the name of the file
      f=fopen(filename,"rb");             // open the file (might be binary)
      send(fd,header,strlen(header),0);   // send the header
                                          //
    	//file size
		long lSize;
		fseek (f,0,SEEK_END);
		lSize = ftell(f);
		rewind(f);
		
		// allocate memory
		char *buffer;
		buffer = (char*)malloc(sizeof(char)*lSize);
		if (buffer == NULL){
			fputs ("Read error",stderr);
			exit(1);
		}
		
		//copy file to buffer
		size_t result;
		result = fread(buffer,1,lSize,f);
		if (result != lSize){
			fputs("Read error",stderr);
			exit(2);
		}

		//send buffer content to browser
		send(fd,buffer,strlen(buffer),0);	
                                          //
      closesocket(fd);                    // close the socket
		fclose(f); 									//close file
		free (buffer); 							//empty buffer
		return 0;                                      // send the file
                                          //
      //closesocket(fd);                    // close the socket
   }
}

Im not wanting to append a \0, from what I understand if I append a \0 it will break my while loop which is listening for incoming requests.

Thank you for your help, I'm still learning alot I would say C is my weakest language so pardon me if I have misunderstood you.

Thank you for your time and help, I understand the problems you have pointed out however because my grasp of these C functions is very limited I am unsure on the solutions for them.

Any nudge in the right direction would be greatly appreciated, I have been reading alot of information to try and solve this but have been unlucky to date.