Max connections per socket

/* Some preliminaries: */
 
#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
 
int sockfd, newsockfd;   /* fds for socket(), accept() */
struct sockaddr_in serv_addr, cli_addr; /* sockaddr_in from <netinet/in.h> */
long clilen; /* in linux 'int'! */
char buffer[];
 
/* socket() : 
"The socket subroutine creates a socket in the specified AddressFamily and of the specified type.
The socket subroutine returns a descriptor (an integer) that can be used in later subroutines 
that operate on sockets." */
 
sockfd = socket(AF_INET, SOCK_STREAM, 0); /* Address family, type, protocol */
 
/* bind() :
"The bind subroutine assigns a Name parameter to an unnamed socket. 
Sockets created by the socket subroutine are unnamed; 
they are identified only by their address family. 
Subroutines that connect sockets either assign names or use unnamed sockets." 
struct sockaddr comes from <sys/socket.h> */
 
bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr));
 
/* listen() :
"The listen subroutine performs the following activities:
- Identifies the socket that receives the connections. 
- Marks the socket as accepting connections. 
- Limits the number of outstanding connection requests in the system queue." */
 
listen(sockfd, 5);                      /* 5 = Queue depth! */
 
/* accept() :
"The accept subroutine extracts the first connection on the queue of pending connections, creates a new socket with the same properties as the specified socket, and allocates a new file descriptor for that socket
The accepted socket cannot accept more connections. 
The original socket remains open and can accept more connections"
==> This is what gheist said: 
The number of accepted sockets is limited only by your program or system resources. <== */
 
newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &clilen);
 
/* Now do whatever you want with the accepted socket */
 
read(newsockfd, buffer, 255);
write(newsockfd, "Message xxxxxxxx", 17);
 
/* close the accepted socket */
close(newsockfd);
 
/* At the very end, close the original (listening) socket) */
close(sockfd);

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