A maximum of
backlog incoming connections will be
queued for processing. If a connection request arrives with the queue
full the client may receive an error with an indication of
ECONNREFUSED, or, if the underlying protocol supports
retransmission, the request may be ignored so that retries may succeed.
Note: The maximum number passed to the
backlogparameter highly depends on the underlying platform. On Linux, it is silently truncated to SOMAXCONN. On win32, if passed SOMAXCONN, the underlying service provider responsible for the socket will set the backlog to a maximum reasonable value. There is no standard provision to find out the actual backlog value on this platform.
socket_listen() is applicable only to sockets of type SOCK_STREAM or SOCK_SEQPACKET.