int main(int argc, char **argv) {
// Set Up
int socket_fd, new_socket_fd, num; // file descriptors, and port number
socklen_t client_length; // size of client address
struct sockaddr_in serv_addr, cli_addr;
char buffer[MAXDATASIZE]; // input gets put here
// Set Up Socket
for(num=0;num<CONSIGNMENT;num++) client_names[num]=NULL; // set all to Null
bzero(buffer,MAXDATASIZE); // Set all to zero
socket_fd = socket(AF_INET, SOCK_STREAM, 0); // create a listening socket to the internet
if (socket_fd < 0) error("ERROR opening socket"); // check the socket
bzero((char *) &serv_addr, sizeof(serv_addr)); // sets all values in the serv_addr to 0
serv_addr.sin_family = AF_INET; // set up the information for the server
serv_addr.sin_addr.s_addr = INADDR_ANY;
serv_addr.sin_port = htons(PORT);
if (bind(socket_fd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) error("ERROR on binding"); // check the bind
listen(socket_fd,5); // sets it up for listening, max of 5 waiting connections while one is being handled
client_length = sizeof(cli_addr);
while(1) {
new_socket_fd = accept(socket_fd, (struct sockaddr *) &cli_addr, &client_length); // pause process until client connects
if (new_socket_fd < 0) error("ERROR on accept"); // check new file descriptor
// server and client talks....
close(new_socket_fd);
}
close(socket_fd); // close connections with client
return(0);
}
is the while loop supposed to be like this, the server should be able to connect with any number of clients, and any of the clients should be about to talk to the server at any time...
That will work but the server will only be able to talk to one client at a time. If you want to handle several simultaneous connections, you'll need to fork() like this:
Code:
int maxproc=5; // Max # of simultaneous connections
{
int newfd=accept(sock);
// Handle children without blocking
while(waitpid(-1, NULL, WNOHANG) >= 0)
{
maxproc++;
}
// If you've exceeded the maximum, actually wait
if(maxproc <= 0) waitpid(-1, NULL, 0);
switch(fork())
{
case -1: // Error
perror("Couldn't fork");
close(newfd);
break;
default: // Parent
maxproc--;
close(newfd);
break;
case 0: // child
do_stuff();
exit(0);
break;
}
}
---------- Post updated at 09:09 PM ---------- Previous update was at 07:46 PM ----------
how does the select function code work? will it achieve a better result than what you proposed?
also
when running my program, i notice that it works usually, but sometimes the output comes out incomplete even when i haven't changed my code...
i think this may have to do with my code for reading and writing from the sockets
this is what i have, are there any errors?
Code:
void send_message(int *client_socket_fd, char *message, int length) {
if (write(*client_socket_fd, message, length) < 0) error("ERROR writing to socket");
}
void read_message(int *socket_fd, char *buffer, int display) {
size_t bytes;
if((bytes = read(*socket_fd, buffer, MAXDATASIZE)) < 0) error("ERROR reading from socket");
if (display) write(1,buffer,bytes);
}
display is either 0 or 1 depending on if i want it to be printed to stdout
so after reading from the socket, does the all the data form the socket get removed, or is it better if i manually remove it, maybe if i do that it will fix my problem?
In this function, this line:
write(1, buffer, str_len(buffer)); write(1, " connected!\n", 12);
is making the client not read everything from the socket
right now, that line is in the right spot to avoid this problem, but if i move that line one line up or 2 lines up, then the client only reads some of the output.
That can't possibly be your complete code. str_len, add_client, send_message, and read_message aren't defined anywhere.
If you don't know what's going wrong, you don't know why it's going wrong, and don't know what I need to see. Chopping bits out of your code just wastes your time and ours.
hai guys,
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Since i am new to this i am asking this.
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