-i [i] This option selects the listing of files any of whose Internet address matches the address
specified in i. If no address is specified, this option selects the listing of all Internet and
x.25 (HP-UX) network files.
If -i4 or -i6 is specified with no following address, only files of the indicated IP version,
IPv4 or IPv6, are displayed. (An IPv6 specification may be used only if the dialects supports
IPv6, as indicated by ``'' and ``IPv'' in lsof's -h or -? output.) Sequentially
specifying -i4, followed by -i6 is the same as specifying -i, and vice-versa. Specifying -i4,
or -i6 after -i is the same as specifying -i4 or -i6 by itself.
Multiple addresses (up to a limit of 100) may be specified with multiple -i options. (A port
number or service name range is counted as one address.) They are joined in a single ORed set
before participating in AND option selection.
An Internet address is specified in the form (Items in square brackets are optional.):
46 specifies the IP version, IPv4 or IPv6
that applies to the following address.
'6' may be be specified only if the UNIX
dialect supports IPv6. If neither '4' nor
'6' is specified, the following address
applies to all IP versions.
protocol is a protocol name - TCP, UDP
hostname is an Internet host name. Unless a
specific IP version is specified, open
network files associated with host names
of all versions will be selected.
hostaddr is a numeric Internet IPv4 address in
dot form; or an IPv6 numeric address in
colon form, enclosed in brackets, if the
UNIX dialect supports IPv6. When an IP
version is selected, only its numeric
addresses may be specified.
service is an /etc/services name - e.g., smtp -
or a list of them.
port is a port number, or a list of them.
IPv6 options may be used only if the UNIX dialect supports IPv6. To see if the dialect supports
IPv6, run lsof and specify the -h or -? (help) option. If the displayed description of the -i
option contains ``'' and ``IPv'', IPv6 is supported.
IPv4 host names and addresses may not be specified if network file selection is limited to IPv6
with -i 6. IPv6 host names and addresses may not be specified if network file selection is
limited to IPv4 with -i 4. When an open IPv4 network file's address is mapped in an IPv6
address, the open file's type will be IPv6, not IPv4, and its display will be selected by '6',
At least one address component - 4, 6, protocol, ,IR hostname , hostaddr, or service - must be
supplied. The `@' character, leading the host specification, is always required; as is the `:',
leading the port specification. Specify either hostname or hostaddr. Specify either service
name list or port number list. If a service name list is specified, the protocol may also need
to be specified if the TCP, UDP and UDPLITE port numbers for the service name are different.
Use any case - lower or upper - for protocol.
Service names and port numbers may be combined in a list whose entries are separated by commas
and whose numeric range entries are separated by minus signs. There may be no embedded spaces,
and all service names must belong to the specified protocol. Since service names may contain
embedded minus signs, the starting entry of a range can't be a service name; it can be a port
Here are some sample addresses:
-i6 - IPv6 only
TCP:25 - TCP and port 25
@126.96.36.199 - Internet IPv4 host address 188.8.131.52
@[3ffe:1ebc::1]:1234 - Internet IPv6 host address
3ffe:1ebc::1, port 1234
UDP:who - UDP who service port
TCP@lsof.itap:513 - TCP, port 513 and host name lsof.itap
tcp@foo:1-10,smtp,99 - TCP, ports 1 through 10,
service name smtp, port 99, host name foo
tcp@bar:1-smtp - TCP, ports 1 through smtp, host bar
:time - either TCP, UDP or UDPLITE time service port
A pipeline is a sequence of one or more commands separated by one of the control operators | or |&. The
format for a pipeline is:
[time [-p]] [ ! ] command [ [|⎪|&] command2 ... ]
The standard output of command is connected via a pipe to the standard input of command2. This
connection is performed before any redirections specified by the command (see REDIRECTION below). If |&
is used, the standard error of command is connected to command2's standard input through the pipe; it is
shorthand for 2>&1 |. This implicit redirection of the standard error is performed after any
redirections specified by the command.
The return status of a pipeline is the exit status of the last command, unless the pipefail option is
enabled. If pipefail is enabled, the pipeline's return status is the value of the last (rightmost)
command to exit with a non-zero status, or zero if all commands exit successfully. If the reserved word
! precedes a pipeline, the exit status of that pipeline is the logical negation of the exit status as
described above. The shell waits for all commands in the pipeline to terminate before returning a value.
If the time reserved word precedes a pipeline, the elapsed as well as user and system time consumed by
its execution are reported when the pipeline terminates. The -p option changes the output format to that
specified by POSIX. When the shell is in posix mode, it does not recognize time as a reserved word if
the next token begins with a `-'. The TIMEFORMAT variable may be set to a format string that specifies
how the timing information should be displayed; see the description of TIMEFORMAT under Shell Variables
When the shell is in posix mode, time may be followed by a newline. In this case, the shell displays the
total user and system time consumed by the shell and its children. The TIMEFORMAT variable may be used
to specify the format of the time information.
Each command in a pipeline is executed as a separate process (i.e., in a subshell).