Listen for connections on a socket
#include <sys/socket.h> int listen( int s, int backlog );
- The descriptor for the socket that you want to listen on. You can create a socket by calling socket().
- The maximum length that the queue of pending connections may grow to.
Use the -l socket option to qcc to link against this library.
The listen() function listens for connections on a socket and puts the socket into the LISTEN state. For connections to be accepted, you must:
- Create a socket by calling socket().
- Indicate a willingness to accept incoming connections and a queue limit for them by calling listen().
- Call accept() to accept the connections.
If a connection request arrives with the queue full, the client may receive an error with an indication of ECONNREFUSED. But if the underlying protocol supports retransmission, the request may be ignored so that retries may succeed.
- An error occurred (errno is set).
- Invalid descriptor s.
- The socket isn't of a type that supports the listen() operation.