他山之石,可以攻玉,该文章将详细地介绍了在Linux 系统中使用TSC 时钟精确地计算一段代码过程(中断和函数等)执行时间需要注意的内容,可以配置Intel 官方文档《How to Benchmark Code Execution Times on Intel® IA-32 and IA-64 Instruction Set Architectures》一起阅读。下面是译文。
Specifies that connections to the given TCP port or Unix socket on the remote (server) host are to be forwarded to the local side.
This works by allocating a socket to listen to either a TCP port or to a Unix socket on the remote side. Whenever a connection is made to this port or Unix socket, the connection is forwarded over the secure channel, and a connection is made from the local machine to either an explicit destination specified by host port hostport, or local_socket, or, if no explicit destination was specified, ssh will act as a SOCKS 4/5 proxy and forward connections to the destinations requested by the remote SOCKS client. Port forwardings can also be specified in the configuration file. Privileged ports can be forwarded only when logging in as root on the remote machine. IPv6 ad‐ dresses can be specified by enclosing the address in square brackets.
By default, TCP listening sockets on the server will be bound to the loopback interface only. This may be overridden by specifying a bind_address. An empty bind_address, or the address ‘*’, indicates that the remote socket should listen on all interfaces. Specifying a remote bind_address will only succeed if the server's GatewayPorts option is enabled (see sshd_config(5)).
If the port argument is ‘0’, the listen port will be dynamically allocated on the server and reported to the client at run time. When used together with -O forward the allocated port will be printed to the standard output.