如果在初始化连接之前，客户端进程没有显式发布bind系统调用，则堆栈负责本地套接字上的隐式绑定。

If the client process has not explicitly issued a bind system call before initiating the connection, implicit binding on the local socket is taken care of by the stack.

youdao

bind调用将进程指定的本地地址复制到mbuf，并调用sobind，后者则根据请求使用PRU_BIND调用tcp_usrreq 。

The bind call copies the local address specified by the process into an mbuf and calls sobind, which in turn calls tcp_usrreq with PRU_BIND as the request.

youdao

本地客户端与服务器的通讯是通过直接的函数调用和消息队列，因为他们在同一个进程中。

The LocalClient communicates with the (local) server through direct function calls and message queues, since it is in the same process.

youdao