在freebsd下sockstat命令可以查看當前系統偵聽端口的程序。和已建立的連接等。其格式如下
SOCKSTAT(1) FreeBSD General Commands Manual SOCKSTAT(1)
NAME
sockstat -- list open sockets
SYNOPSIS
sockstat [-46clu] [-p ports]
DESCRIPTION
The sockstat command lists open Internet or UNIX domain sockets.
The following options are available:
-4 Show AF_INET (IPv4) sockets.
-6 Show AF_INET6 (IPv6) sockets.
-c Show connected sockets.
-l Show listening sockets.
-p ports Only show Internet sockets if either the local or foreign
port number is on the specified list. The ports argument is
a comma-separated list of port numbers and ranges specified
as first and last port separated by a dash.
-u Show AF_LOCAL (UNIX) sockets.
If neither -4, -6 or -u is specified, sockstat will list sockets in all
three domains.
If neither -c or -l is specified, sockstat will list both listening and
connected sockets.
The information listed for each socket is:
USER The user who owns the socket.
COMMAND The command which holds the socket.
PID The process ID of the command which holds the socket.
FD The file descriptor number of the socket.
PROTO The transport protocol associated with the socket for
Internet sockets, or the type of socket (stream or data-
gram) for UNIX sockets.
LOCAL ADDRESS For Internet sockets, this is the address the local end
of the socket is bound to (see getsockname(2)). For
bound UNIX sockets, it is the socket's filename. For
other UNIX sockets, it is a right arrow followed by the
endpoint's filename, or ``??'' if the endpoint could not
be determined.
FOREIGN ADDRESS (Internet sockets only) The address the foreign end of
the socket is bound to (see getpeername(2)).
Note that TCP sockets in the AF_INET or AF_INET6 domains that are not in
one of the LISTEN, SYN_SENT, or ESTABLISHED states may not be shown by
sockstat; use netstat(1) to examine them instead.
簡單地說
sockstat -4l ——可以查看偵聽端口的程序，其中4表示ipv4，l表示listen
sockstat -4c ——可以查看已建立的連接狀況。
sockstat -4 ——等於上述兩個命令的和。
