Page 76 . 5.4 監聽socket
此處作者說法不完整。
通過Google "man listen " http://linux.die.net/man/2/listen
listen() marks the socket referred to by sockfd as a passive socket, that is, as a socket that will be used to accept incoming connection requests using accept(2).The sockfd argument is a file descriptor that refers to a socket of type SOCK_STREAM or SOCK_SEQPACKET.
The backlog argument defines the maximum length to which the queue of pending connections for sockfd may grow. If a connection request arrives when the queue is 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 a later reattempt at connection succeeds.
可見與實現有關。
書的內容還是很全的，但作者的觀點略感覺不對。 服務器中用信號來通知的，或者說來做異步的，就我了解是幾乎沒有。 作者去花了很多篇幅去介紹。
讓人感覺完全是為了湊字數啊。 書名里面的“高性能”要打個折扣了