SOCKSTAT(1) FreeBSD General Commands Manual SOCKSTAT(1)
NAME
sockstat - list open sockets
SYNOPSIS
sockstat [--libxo] [-46AbCcfIiLlnqSsUuvw] [-j jail] [-p ports]
[-P protocols]
DESCRIPTION
The sockstat command lists open Internet or Unix domain sockets.
The following options are available:
--libxo Generate output via libxo(3) in a selection of different
human and machine readable formats. See xo_options(7) for
details on command line arguments.
-4 Show AF_INET (IPv4) sockets.
-6 Show AF_INET6 (IPv6) sockets.
-A Show the address of a protocol control block (PCB) associated
with a socket; used for debugging.
-b Show the BBLog state of the socket. This is currently only
implemented for TCP.
-C Display the congestion control module, if applicable. This
is currently only implemented for TCP.
-c Show connected sockets.
-f Show the FIB number of each socket.
-I Show the local address of the socket to which the current
socket is spliced, if any. See the setsockopt(2) SO_SPLICE
option for more information.
-i Display the inp_gencnt.
-j jail Show only sockets belonging to the specified jail ID or name.
-L Only show Internet sockets if the local and foreign addresses
are not in the loopback network prefix 127.0.0.0/8, or do not
contain the IPv6 loopback address ::1.
-l Show listening sockets.
-n Do not resolve numeric UIDs to user names.
-p ports Only show Internet sockets if 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.
-P protocols
Only show sockets of the specified protocols. The protocols
argument is a comma-separated list of protocol names, as they
are defined in protocols(5).
-q Quiet mode, do not print the header line.
-S Display the protocol stack, if applicable. This is currently
only implemented for TCP.
-s Display the protocol state, if applicable. This is currently
only implemented for SCTP and TCP.
-U Display the remote UDP encapsulation port number, if
applicable. This is currently only implemented for SCTP and
TCP.
-u Show AF_LOCAL (Unix) sockets.
-v Verbose mode.
-w Automatically size the columns.
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,
datagram, or seqpacket) 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, socket's filename is printed.
For not bound Unix sockets, the field is empty.
FOREIGN ADDRESS For Internet sockets, this is the address the foreign
end of the socket is bound to (see getpeername(2)).
For bound Unix sockets a left arrow followed by the peer
list is printed. For Unix sockets that went through
connect(2) system call a right arrow followed by the
peer is printed. Peers are printed in square brackets
as [PID FD].
ID The inp_gencnt if -i is specified (only for TCP or UDP).
ENCAPS The remote UDP encapsulation port number if -U is
specified (only for SCTP or TCP).
PATH STATE The path state if -s is specified (only for SCTP). When
using traditional text output, this column is only shown
when there is at least one path state to show.
CONN STATE The connection state if -s is specified (only for SCTP
or TCP).
BBLOG STATE The BBLog state if -b is specified (only for TCP).
STACK The protocol stack if -S is specified (only for TCP).
CC The congestion control if -C is specified (only for
TCP).
If a socket is associated with more than one file descriptor, it is shown
multiple times. If a socket is not associated with any file descriptor,
the first four columns have no meaning.
EXAMPLES
Show information for IPv4 sockets listening on port 22 using protocol
TCP:
$ sockstat -4 -l -P tcp -p 22
Show information for sockets using either TCP or UDP, if neither, the
local nor the foreign addresses are in the loopback network:
$ sockstat -L -P tcp,udp
Show TCP IPv6 sockets which are listening and connected (default):
$ sockstat -6 -P tcp
Show all sockets in JSON format with neat alignment:
$ sockstat --libxo json,pretty
SEE ALSO
fstat(1), netstat(1), procstat(1), setfib(1), libxo(3), inet(4),
inet6(4), protocols(5), xo_options(7)
HISTORY
The sockstat command appeared in FreeBSD 3.1.
AUTHORS
The sockstat command and this manual page were written by Dag-Erling
Smorgrav <des@FreeBSD.org>.
FreeBSD 15.1-STABLE-HBSD April 15, 2026 SOCKSTAT(1)