LSOF
Section: Maintenance Commands (8)
Updated: Revision-4.81
NAME
lsof - list open files
SYNOPSIS
lsof
[
-?abChlnNOPRtUvVX
] [
-A A
] [
-c c
] [
+c c
] [
+|-d d
] [
+|-D D
] [
+|-f [cfgGn]
] [
-F [f]
] [
-g [s]
] [
-i [i]
] [
-k k
] [
+|-L [l]
] [
+|-m m
] [
+|-M
] [
-o [o]
] [
-p s
] [
+|-r [t[m<fmt>]]
] [
-s [p:s]
] [
-S [t]
] [
-T [t]
] [
-u s
] [
+|-w
] [
-x [fl]
] [
-z [z]
] [
-Z [Z]
] [
--
] [names]
DESCRIPTION
Lsof
revision 4.81 lists on its standard output file information about files
opened by processes for the following UNIX dialects:
AIX 5.3
FreeBSD 4.9 for x86-based systems
FreeBSD 7.0 and 8.0 for AMD64-based systems
Linux 2.1.72 and above for x86-based systems
Solaris 9 and 10
(See the
DISTRIBUTION
section of this manual page for information on how to obtain the
latest
lsof
revision.)
An open file may be a regular file, a directory, a block special file,
a character special file, an executing text reference, a library,
a stream or a network file (Internet socket, NFS file or UNIX domain socket.)
A specific file or all the files in a file system may be selected by path.
Instead of a formatted display,
lsof
will produce output that can be parsed by other programs.
See the
-F,
option description, and the
OUTPUT FOR OTHER PROGRAMS
section for more information.
In addition to producing a single output list,
lsof
will run in repeat mode.
In repeat mode it will produce output, delay, then repeat the output
operation until stopped with an interrupt or quit signal.
See the
+|-r [t[m<fmt>]]
option description for more information.
OPTIONS
In the absence of any options,
lsof
lists all open files belonging to all active processes.
If any list request option is specified, other list requests must be
specifically requested - e.g., if
-U
is specified for the listing of UNIX socket files, NFS files won't be
listed unless
-N
is also specified;
or if a user list is specified with the
-u
option, UNIX domain socket files, belonging to users not in the list,
won't be listed unless the
-U
option is also specified.
Normally list options that are specifically stated are ORed - i.e.,
specifying the
-i
option without an address and the -ufoo option produces a
listing of all network files OR files belonging to processes owned
by user ``foo''.
The exceptions are:
-
- 1)
-
the `^' (negated) login name or user ID (UID), specified with the
-u
option;
- 2)
-
the `^' (negated) process ID (PID), specified with the
-p
option;
- 3)
-
the `^' (negated) process group ID (PGID), specified with the
-g
option;
- 4)
-
the `^' (negated) command, specified with the
-c
option;
- 5)
-
the ('^') negated TCP or UDP protocol state names, specified with the
-s [p:s]
option.
Since they represent exclusions, they are applied without ORing or ANDing
and take effect before any other selection criteria are applied.
The
-a
option may be used to AND the selections.
For example, specifying
-a,
-U,
and -ufoo produces a listing of only UNIX socket files that
belong to processes owned by user ``foo''.
Caution: the
-a
option causes all list selection options to be ANDed; it can't
be used to cause ANDing of selected pairs of selection options
by placing it between them, even though its placement there is
acceptable.
Wherever
-a
is placed, it causes the ANDing of all selection options.
Items of the same selection set - command names, file descriptors,
network addresses, process identifiers, user identifiers, zone names,
security contexts - are joined in a single ORed set and applied
before the result participates in ANDing.
Thus, for example, specifying -i@aaa.bbb, -i@ccc.ddd,
-a,
and -ufff,ggg will select the listing of files that belong to
either login ``fff'' OR ``ggg'' AND have network connections to either
host aaa.bbb OR ccc.ddd.
Options may be grouped together following a single prefix -- e.g.,
the option set ``-a -b -C'' may be stated as
-abC.
However, since values are optional following
+|-f,
-F,
-g,
-i,
+|-L,
-o,
+|-r,
-s,
-S,
-T,
-x
and
-z.
when you have no values for them be careful that the
following character isn't ambiguous.
For example,
-Fn
might represent the
-F
and
-n
options, or it might represent the
n
field identifier character following the
-F
option.
When ambiguity is possible, start a new option with a `-'
character - e.g., ``-F -n''.
If the next option is a file name, follow the possibly ambiguous
option with ``--'' - e.g., ``-F -- name''.
Either the `+' or the `-' prefix may be applied to a group of options.
Options that don't take on separate meanings for each
prefix - e.g., -i - may be grouped under either prefix.
Thus, for example, ``+M -i'' may be stated as ``+Mi'' and the group
means the same as the separate options.
Be careful of prefix grouping when one or more options in the group
does take on separate meanings under different prefixes -
e.g., +|-M; ``-iM'' is not the same request as ``-i +M''.
When in doubt, use separate options with appropriate prefixes.
- -? -h
-
These two equivalent options select a usage (help) output list.
Lsof
displays a shortened form of this output when it detects an error
in the options supplied to it, after it has displayed messages
explaining each error.
(Escape the `?' character as your shell requires.)
- -a
-
This option causes list selection options to be ANDed, as described
above.
- -A A
-
This option is available on systems configured for AFS whose AFS
kernel code is implemented via dynamic modules.
It allows the
lsof
user to specify
A
as an alternate name list file where the kernel addresses of the dynamic
modules might be found.
See the
lsof
FAQ (The FAQ section gives its location.)
for more information about dynamic modules, their
symbols, and how they affect
lsof.
- -b
-
This option causes
lsof
to avoid kernel functions that might block -
lstat(2),
readlink(2),
and
stat(2).
-
See the
BLOCKS AND TIMEOUTS
and
AVOIDING KERNEL BLOCKS
sections for information on using this option.
- -c c
-
This option selects the listing of files for processes executing the
command that begins with the characters of
c.
Multiple commands may be specified, using multiple
-c
options.
They are joined in a single ORed set before participating in
AND option selection.
-
If
c
begins with a '^', then the following characters specify a command
name whose processes are to be ignored (excluded.)
-
If
c
begins and ends with a slash ('/'), the characters between the slashes
are interpreted as a regular expression.
Shell meta-characters in the regular expression must be quoted to prevent
their interpretation by the shell.
The closing slash may be followed by these modifiers:
-
b the regular expression is a basic one.
i ignore the case of letters.
x the regular expression is an extended one
(default).
-
See the
lsof
FAQ (The FAQ section gives its location.)
for more information on basic and extended regular
expressions.
-
The simple command specification is tested first.
If that test fails, the command regular expression is applied.
If the simple command test succeeds, the command regular expression
test isn't made.
This may result in ``no command found for regex:'' messages
when lsof's
-V
option is specified.
- +c w
-
This option defines the maximum number of initial characters of the name,
supplied by the UNIX dialect, of the UNIX command associated with a process
to be printed in the COMMAND column.
(The
lsof
default is nine.)
-
Note that many UNIX dialects do not supply all command name characters
to
lsof
in the files and structures from which
lsof
obtains command name.
Often dialects limit the number of characters supplied in those sources.
For example, Linux 2.4.27 and Solaris 9 both limit command name length to
16 characters.
-
If
w
is zero ('0'), all command characters supplied to
lsof
by the UNIX dialect will be printed.
-
If
w
is less than the length of the column title, ``COMMAND'', it will
be raised to that length.
- -C
-
This option disables the reporting of any path name
components from the kernel's name cache.
See the
KERNEL NAME CACHE
section for more information.
- +d s
-
This option causes
lsof
to search for all open instances of directory
s
and the files and directories it contains at its top level.
This option does NOT descend the directory tree, rooted at
s.
The
+D D
option may be used to request a full-descent directory tree search,
rooted at directory
D.
-
Processing of the
+d
option does not follow symbolic links within
s
unless the
-x
or
-x l
option is also specified.
Nor does it
search for open files on file system mount points on subdirectories of
s
unless the
-x
or
-x f
option is also specified.
-
Note: the authority of the user of this option limits it to searching for
files that the user has permission to examine with the system
stat(2)
function.
- -d s
-
This option specifies a list of file descriptors (FDs) to exclude from
or include in the output listing.
The file descriptors are specified in the comma-separated set
s
- e.g., ``cwd,1,3'', ``^6,^2''.
(There should be no spaces in the set.)
-
The list is an exclusion list if all entries of the set begin with '^'.
It is an inclusion list if no entry begins with '^'.
Mixed lists are not permitted.
-
A file descriptor number range may be in the set as long as
neither member is empty, both members are numbers, and the ending
member is larger than the starting one - e.g., ``0-7'' or ``3-10''.
Ranges may be specified for exclusion if they have the '^' prefix -
e.g., ``^0-7'' excludes all file descriptors 0 through 7.
-
Multiple file descriptor numbers are joined in a single ORed set before
participating in AND option selection.
-
When there are exclusion and inclusion members in the set,
lsof
reports them as errors and exits with a non-zero return code.
-
See the description of File Descriptor (FD) output values in the
OUTPUT
section for more information on file descriptor names.
- +D D
-
This option causes
lsof
to search for all open instances of directory
D
and all the files and directories it contains to its complete depth.
-
Processing of the
+D
option does not follow symbolic links within
D
unless the
-x
or
-x l
option is also specified.
Nor does it
search for open files on file system mount points on subdirectories of
D
unless the
-x
or
-x f
option is also specified.
-
Note: the authority of the user of this option limits it to searching for
files that the user has permission to examine with the system
stat(2)
function.
-
Further note:
lsof
may process this option slowly and require a large amount of dynamic memory
to do it.
This is because it must descend the entire directory tree, rooted at
D,
calling
stat(2)
for each file and directory, building a list of all the files it finds, and
searching that list for a match with every open file.
When directory
D
is large, these steps can take a long time, so use this option prudently.
- -D D
-
This option directs
lsof's
use of the device cache file.
The use of this option is sometimes restricted.
See the
DEVICE CACHE FILE
section and the sections that follow it for more information on this
option.
-
-D
must be followed by a function letter; the function letter may optionally
be followed by a path name.
Lsof
recognizes these function letters:
-
? - report device cache file paths
b - build the device cache file
i - ignore the device cache file
r - read the device cache file
u - read and update the device cache file
-
The
b,
r,
and
u
functions, accompanied by a path name, are sometimes restricted.
When these functions are restricted, they will not appear in
the description of the
-D
option that accompanies
-h
or
-?
option output.
See the
DEVICE CACHE FILE
section and the sections that follow it for more information on these
functions and when they're restricted.
-
The
?
function reports the read-only and write paths that lsof can
use for the device cache file,
the names of any environment variables whose values
lsof
will examine when forming the device cache file path,
and the format for the personal device cache file path.
(Escape the `?' character as your shell requires.)
-
When available, the
b,
r,
and
u
functions may be followed by the device cache file's path.
The standard default is
.lsof_hostname
in the home directory of the real user ID that executes
lsof,
but this could have been changed when
lsof
was configured and compiled.
(The output of the
-h
and
-?
options show the current default prefix - e.g., ``.lsof''.)
The suffix,
hostname,
is the first component of the host's name returned by
gethostname(2).
-
When available, the
b
function directs
lsof
to build a new device cache file at the default or specified path.
-
The
i
function directs
lsof
to ignore the default device cache file and obtain its information
about devices via direct calls to the kernel.
-
The
r
function directs
lsof
to read the device cache at the default or specified path, but
prevents it from creating a new device cache file when none
exists or the existing one is improperly structured.
The
r
function, when specified without a path name, prevents
lsof
from updating an incorrect or outdated device cache file,
or creating a new one in its place.
The
r
function is always available when it is specified without a
path name argument; it may be restricted by the permissions of the
lsof
process.
-
When available, the
u
function directs
lsof
to read the device cache file at the default or specified path,
if possible, and to rebuild it, if necessary.
This is the default device cache file function when no
-D
option has been specified.
- +|-f [cfgGn]
-
f
by itself clarifies how path name arguments are to be interpreted.
When followed by
c,
f,
g,
G,
or
n
in any combination it specifies
that the listing of kernel file structure information is to be enabled
(`+') or inhibited (`-').
-
Normally a path name argument is taken to be a file system name if
it matches a mounted-on directory name reported by
mount(8),
or if it represents a block device, named in the
mount
output and associated with a mounted directory name.
When
+f
is specified, all path name arguments will be taken to be file
system names, and
lsof
will complain if any are not.
This can be useful, for example, when the file system name
(mounted-on device) isn't a block device.
This happens for some CD-ROM file systems.
-
When
-f
is specified by itself, all path name arguments will be taken to be
simple files.
Thus, for example, the ``-f -- /'' arguments direct lsof to search
for open files with a `/' path name, not all open files in the `/'
(root) file system.
-
Be careful to make sure
+f
and
-f
are properly terminated and aren't followed by a character (e.g., of
the file or file system name) that might be taken as a parameter.
For example, use ``--'' after
+f
and
-f
as in these examples.
-
$ lsof +f -- /file/system/name
$ lsof -f -- /file/name
-
The listing of information from kernel file structures, requested with the
+f [cfgGn]
option form, is normally
inhibited, and is not available in whole or part for some dialects - e.g.,
/proc-based Linux kernels below 2.6.22.
When the prefix to
f
is a plus sign (`+'), these characters request file structure information:
-
c file structure use count (not Linux)
f file structure address (not Linux)
g file flag abbreviations (Linux 2.6.22 and up)
G file flags in hexadecimal (Linux 2.6.22 and up)
n file structure node address (not Linux)
-
When the prefix is minus (`-') the same characters disable the
listing of the indicated values.
-
File structure addresses, use counts, flags, and node addresses may be
used to detect more readily identical files inherited by child
processes and identical files in use by different processes.
Lsof
column output can be sorted by output columns holding the values
and listed to identify identical file use, or
lsof
field output can be parsed by an AWK or Perl post-filter script,
or by a C program.
- -F f
-
This option specifies a character list,
f,
that selects the fields to be output for processing by another program,
and the character that terminates each output field.
Each field to be output is specified with a single character in
f.
The field terminator defaults to NL, but may be changed to NUL (000).
See the
OUTPUT FOR OTHER PROGRAMS
section for a description of the field identification characters and
the field output process.
-
When the field selection character list is empty, all standard fields are
selected (except the raw device field, security context and zone field for
compatibility reasons)
and the NL field terminator is used.
-
When the field selection character list contains only a zero (`0'),
all fields are selected (except the raw device field for compatibility
reasons) and the NUL terminator character is used.
-
Other combinations of fields and their associated field terminator
character must be set with explicit entries in
f,
as described in the
OUTPUT FOR OTHER PROGRAMS
section.
-
When a field selection character identifies an item
lsof
does not normally list - e.g., PPID, selected with
-R -
specification of the field character - e.g., ``-FR'' -
also selects the listing of the item.
-
When the field selection character list contains the single
character `?',
lsof
will display a help list of the field identification characters.
(Escape the `?' character as your shell requires.)
- -g [s]
-
This option excludes or selects the listing of files for the processes
whose optional process group IDentification (PGID) numbers are in the
comma-separated set
s
- e.g., ``123'' or ``123,^456''.
(There should be no spaces in the set.)
-
PGID numbers that begin with `^' (negation) represent exclusions.
-
Multiple PGID numbers are joined in a single ORed set before participating
in AND option selection.
However, PGID exclusions are applied without ORing or ANDing
and take effect before other selection criteria are applied.
-
The
-g
option also enables the output display of PGID numbers.
When specified without a PGID set that's all it does.
- -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 ``[46]'' and ``IPv[46]'' 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][protocol][@hostname|hostaddr][:service|port]
-
where:
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 ``[46]'' and ``IPv[46]'', 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', not '4'.
-
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 number, however.
-
Here are some sample addresses:
-i6 - IPv6 only
TCP:25 - TCP and port 25
@1.2.3.4 - Internet IPv4 host address 1.2.3.4
@[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
- -k k
-
This option specifies a kernel name list file,
k,
in place of /vmunix, /mach, etc.
This option is not available under AIX on the IBM RISC/System 6000.
- -l
-
This option inhibits the conversion of user ID numbers to login names.
It is also useful when login name lookup is working improperly or slowly.
- +|-L [l]
-
This option enables (`+') or disables (`-') the listing of file link
counts, where they are available - e.g., they aren't available
for sockets, or most FIFOs and pipes.
-
When
+L
is specified without a following number, all link counts will be listed.
When
-L
is specified (the default), no link counts will be listed.
-
When
+L
is followed by a number, only files having a link count less than
that number will be listed.
(No number may follow
-L.)
A specification of the form ``+L1'' will select open files that
have been unlinked.
A specification of the form ``+aL1 <file_system>'' will select
unlinked open files on the specified file system.
-
For other link count comparisons, use field output (-F)
and a post-processing script or program.
- +|-m m
-
This option specifies an alternate kernel memory file or activates
mount table supplement processing.
-
The option form
-m m
specifies a kernel memory file,
m,
in place of
/dev/kmem
or
/dev/mem
- e.g., a crash dump file.
-
The option form
+m
requests that a mount supplement file be written to the standard output
file.
All other options are silently ignored.
-
There will be a line in the mount supplement file for each mounted file
system, containing the mounted file system directory, followed by a single
space, followed by the device number in hexadecimal "0x" format - e.g.,
-
/ 0x801
-
Lsof
can use the mount supplement file to get device numbers for file systems
when it can't get them via
stat(2)
or
lstat(2).
-
The option form
+m m
identifies
m
as a mount supplement file.
-
Note: the
+m
and
+m m
options are not available for all supported dialects.
Check the output of
lsof's
-h
or
-?
options to see if the
+m
and
+m m
options are available.
- +|-M
-
Enables (+) or disables (-) the
reporting of portmapper registrations for local TCP, UDP and UDPLITE ports.
The default reporting mode is set by the
lsof
builder with the HASPMAPENABLED #define in the dialect's machine.h
header file;
lsof
is distributed with the HASPMAPENABLED #define deactivated, so
portmapper reporting is disabled by default and must be requested
with
+M.
Specifying
lsof's
-h
or
-?
option will report the default mode.
Disabling portmapper registration when it is already disabled or
enabling it when already enabled is acceptable.
-
When portmapper registration reporting is enabled,
lsof
displays the portmapper registration (if any) for local TCP, UDP or
UDPLITE ports
in square brackets immediately following the port numbers or service
names - e.g., ``:1234[name]'' or ``:name[100083]''.
The registration information may be a name or number, depending
on what the registering program supplied to the portmapper when
it registered the port.
-
When portmapper registration reporting is enabled,
lsof
may run a little more slowly or even become blocked when access to the
portmapper becomes congested or stopped.
Reverse the reporting mode to determine if portmapper registration
reporting is slowing or blocking
lsof.
-
For purposes of portmapper registration reporting
lsof
considers a TCP, UDP or UDPLITE port local if: it is found in the local part
of its containing kernel structure;
or if it is located in the foreign part of its containing kernel
structure and the local and foreign Internet addresses are the same;
or if it is located in the foreign part of its containing kernel
structure and the foreign Internet address is INADDR_LOOPBACK (127.0.0.1).
This rule may make
lsof
ignore some foreign ports on machines with multiple interfaces
when the foreign Internet address is on a different interface
from the local one.
-
See the
lsof
FAQ (The FAQ section gives its location.)
for further discussion of portmapper registration
reporting issues.
- -n
-
This option inhibits the conversion of network numbers to
host names for network files.
Inhibiting conversion may make
lsof
run faster.
It is also useful when host name lookup is not working properly.
- -N
-
This option selects the listing of NFS files.
- -o
-
This option directs
lsof
to display file offset at all times.
It causes the SIZE/OFF output column title to be changed to OFFSET.
Note: on some UNIX dialects
lsof
can't obtain accurate or consistent file offset information from its
kernel data sources, sometimes just for particular kinds of files
(e.g., socket files.)
Consult the
lsof
FAQ (The FAQ section gives its location.)
for more information.
-
The
-o
and
-s
options are mutually exclusive; they can't both be specified.
When neither is specified,
lsof
displays whatever value - size or offset - is appropriate and
available for the type of the file.
- -o o
-
This option defines the number of decimal digits (o) to be
printed after the ``0t'' for a file offset before the form is switched
to ``0x...''.
An
o
value of zero (unlimited) directs
lsof
to use the ``0t'' form for all offset output.
-
This option does NOT direct
lsof
to display offset at all times; specify
-o
(without a trailing number) to do that.
This option only specifies the number of digits after ``0t'' in
either mixed size and offset or offset-only output.
Thus, for example, to direct
lsof
to display offset at all times with a decimal digit count of 10, use:
-
-o -o 10
or
-oo10
-
The default number of digits allowed after ``0t'' is normally 8,
but may have been changed by the lsof builder.
Consult the description of the
-o o
option in the output of the
-h
or
-?
option to determine the default that is in effect.
- -O
-
This option directs
lsof
to bypass the strategy it uses to avoid being blocked by some
kernel operations - i.e., doing them in forked child processes.
See the
BLOCKS AND TIMEOUTS
and
AVOIDING KERNEL BLOCKS
sections for more information on kernel operations that may block
lsof.
-
While use of this option will reduce
lsof
startup overhead, it may also cause
lsof
to hang when the kernel doesn't respond to a function.
Use this option cautiously.
- -p s
-
This option excludes or selects the listing of files for the processes
whose optional process IDentification (PID) numbers are in the
comma-separated set
s
- e.g., ``123'' or ``123,^456''.
(There should be no spaces in the set.)
-
PID numbers that begin with `^' (negation) represent exclusions.
-
Multiple process ID numbers are joined in a single ORed set before
participating in AND option selection.
However, PID exclusions are applied without ORing or ANDing
and take effect before other selection criteria are applied.
- -P
-
This option inhibits the conversion of port numbers to port
names for network files.
Inhibiting the conversion may make
lsof
run a little faster.
It is also useful when port name lookup is not working properly.
- +|-r [t[m<fmt>]]
-
This option puts
lsof
in repeat mode.
There
lsof
lists open files as selected by other options, delays
t
seconds (default fifteen), then repeats the listing, delaying
and listing repetitively until stopped by a condition defined by
the prefix to the option.
-
If the prefix is a `-', repeat mode is endless.
Lsof
must be terminated with an interrupt or quit signal.
-
If the prefix is `+', repeat mode will end the first cycle no open files
are listed - and of course when
lsof
is stopped with an interrupt or quit signal.
When repeat mode ends because no files are listed, the process exit code
will be zero if any open files were ever listed; one, if none were ever
listed.
-
Lsof
marks the end of each listing:
if field output is in progress (the
-F,
option has been specified), the default marker is `m'; otherwise the
default marker is ``========''.
The marker is followed by a NL character.
-
The optional "m<fmt>" argument specifies a format for the marker line.
The <fmt> characters following `m' are interpreted as a format
specification to the
strftime(3)
function, when both it and the
localtime(3)
function are available in the dialect's C library.
Consult the
strftime(3)
documentation for what may appear in its format specification.
Note that when field output is requested with the
-F
option, <fmt> cannot contain the NL format, ``%n''.
Note also that when <fmt> contains spaces or other characters that
affect the shell's interpretation of arguments, <fmt> must be
quoted appropriately.
-
Repeat mode reduces
lsof
startup overhead, so it is more efficient to use this mode
than to call
lsof
repetitively from a shell script, for example.
-
To use repeat mode most efficiently, accompany
+|-r
with specification of other
lsof
selection options, so the amount of kernel memory access
lsof
does will be kept to a minimum.
Options that filter at the process level - e.g.,
-c,
-g,
-p,
-u
- are the most efficient selectors.
-
Repeat mode is useful when coupled with field output (see the
-F,
option description) and a supervising
awk
or
Perl
script, or a C program.
- -R
-
This option directs lsof to list the Parent Process IDentification
number in the PPID column.
- -s [p:s]
-
s
alone directs
lsof
to display file size at all times.
It causes the SIZE/OFF output column title to be changed to SIZE.
If the file does not have a size, nothing is displayed.
-
When followed by a protocol name (p), either TCP or UDP,
a colon (`:') and a comma-separated protocol state name list,
the option causes open TCP and UDP files to be excluded if their
state name(s) are in the list (s) preceded by a `^'; or
included if their name(s) are not preceded by a `^'.
-
When an inclusion list is defined, only network files with state
names in the list will be present in the
lsof
output.
Thus, specifying one state name means that only network files
with that lone state name wil be listed.
-
Case is unimportant in the protocol or state names, but there may
be no spaces and the colon (`:') separating the protocol
name (p) and the state name list (s) is required.
-
If only TCP and UDP files are to be listed, as controlled by
the specified exclusions and inclusions, the
-i
option must be specified, too.
If only a single protocol's files are to be listed, add its name
as an argument to the
-i
option.
-
For example, to list only network files with TCP state LISTEN, use:
-
-iTCP -sTCP:LISTEN
-
Or, for example, to list network files with all UDP states except
Idle, use:
-
-iUDP -sUDP:Idle
-
State names vary with UNIX dialects, so it's not possible to
provide a complete list. Some common TCP state names are:
CLOSED, IDLE, BOUND, LISTEN, ESTABLISHED, SYN_SENT, SYN_RCDV,
ESTABLISHED, CLOSE_WAIT, FIN_WAIT1, CLOSING, LAST_ACK, FIN_WAIT_2,
and TIME_WAIT.
Two common UDP state names are Unbound and Idle.
-
See the
lsof
FAQ (The FAQ section gives its location.)
for more information on how to use protocol state exclusion and
inclusion, including examples.
-
The
-o
(without a following decimal digit count) and
-s
option (without a following protocol and state name list)
are mutually exclusive; they can't both be specified.
When neither is specified,
lsof
displays whatever value - size or offset - is appropriate and
available for the type of file.
-
Since some types of files don't have true sizes - sockets, FIFOs,
pipes, etc. - lsof displays for their sizes the content amounts in
their associated kernel buffers, if possible.
- -S [t]
-
This option specifies an optional time-out seconds value for kernel functions -
lstat(2),
readlink(2),
and
stat(2)
- that might otherwise deadlock.
The minimum for
t
is two;
the default, fifteen; when no value is specified, the default is used.
-
See the
BLOCKS AND TIMEOUTS
section for more information.
- -T [t]
-
This option controls the reporting of some TCP/TPI information, also
reported by
netstat(1),
following the network addresses.
In normal output the information appears in parentheses, each item
except TCP or TPI state name identified by a keyword, followed by `=',
separated from others by a single space:
-
<TCP or TPI state name>
QR=<read queue length>
QS=<send queue length>
SO=<socket options and values>
SS=<socket states>
TF=<TCP flags and values>
WR=<window read length>
WW=<window write length>
-
Not all values are reported for all UNIX dialects.
Items values (when available) are reported after the item name and '='.
-
When the field output mode is in effect (See
OUTPUT FOR OTHER PROGRAMS.)
each item appears as a field with a `T' leading character.
-
-T
with no following key characters disables TCP/TPI information reporting.
-
-T
with following characters selects the reporting of specific TCP/TPI
information:
-
f selects reporting of socket options,
states and values, and TCP flags and
values.
q selects queue length reporting.
s selects connection state reporting.
w selects window size reporting.
-
Not all selections are enabled for some UNIX dialects.
State may be selected for all dialects and is reported by default.
The
-h
or
-?
help output for the
-T
option will show what selections may be used with the UNIX dialect.
-
When
-T
is used to select information - i.e., it is followed by one or more
selection characters - the displaying of state is disabled by default,
and it must be explicitly selected again in the characters following
-T.
(In effect, then, the default is equivalent to
-Ts.)
For example, if queue lengths and state are desired, use
-Tqs.
-
Socket options, socket states, some socket values, TCP flags and
one TCP value may be reported (when available in the UNIX dialect)
in the form of the names that commonly appear after SO_, so_, SS_,
TCP_ and TF_ in the dialect's header files -
most often <sys/socket.h>, <sys/socketvar.h> and <netinet/tcp_var.h>.
Consult those header files for the meaning of the flags, options,
states and values.
-
``SO='' precedes socket options and values; ``SS='', socket states;
and ``TF='', TCP flags and values.
-
If a flag or option has a value, the value will follow an '=' and
the name -- e.g., ``SO=LINGER=5'', ``SO=QLIM=5'', ``TF=MSS=512''.
The following seven values may be reported:
-
Name
Reported Description (Common Symbol)
KEEPALIVE keep alive time (SO_KEEPALIVE)
LINGER linger time (SO_LINGER)
MSS maximum segment size (TCP_MAXSEG)
PQLEN partial listen queue connections
QLEN established listen queue connections
QLIM established listen queue limit
RCVBUF receive buffer length (SO_RCVBUF)
SNDBUF send buffer length (SO_SNDBUF)
-
Details on what socket options and values, socket states, and TCP flags
and values may be displayed for particular UNIX dialects may be found in
the answer to the ``Why doesn't lsof report socket options, socket states,
and TCP flags and values for my dialect?'' and ``Why doesn't lsof report
the partial listen queue connection count for my dialect?''
questions in the
lsof
FAQ (The FAQ section gives its location.)
- -t
-
This option specifies that
lsof
should produce terse output with process identifiers only and no header -
e.g., so that the output may be piped to
kill(1).
This option selects the
-w
option.
- -u s
-
This option selects the listing of files for the user whose login names
or user ID numbers are in the comma-separated set
s
- e.g., ``abe'',
or ``548,root''.
(There should be no spaces in the set.)
-
Multiple login names or user ID numbers are joined in a single ORed set
before participating in AND option selection.
-
If a login name or user ID is preceded by a `^', it becomes a negation -
i.e., files of processes owned by the login name or user ID will never
be listed.
A negated login name or user ID selection is neither ANDed nor ORed
with other selections; it is applied before all other selections and
absolutely excludes the listing of the files of the process.
For example, to direct
lsof
to exclude the listing of files belonging to root processes,
specify ``-u^root'' or ``-u^0''.
- -U
-
This option selects the listing of UNIX domain socket files.
- -v
-
This option selects the listing of
lsof
version information, including: revision number;
when the
lsof
binary was constructed;
who constructed the binary and where;
the name of the compiler used to construct the
lsof binary;
the version number of the compiler when readily available;
the compiler and loader flags used to construct the
lsof
binary;
and system information, typically the output of
uname's
-a
option.
- -V
-
This option directs
lsof
to indicate the items it was asked to list and failed to find - command
names, file names, Internet addresses or files, login names, NFS files,
PIDs, PGIDs, and UIDs.
-
When other options are ANDed to search options, or compile-time
options restrict the listing of some files,
lsof
may not report that it failed to find a search item when an ANDed
option or compile-time option prevents the listing of the open file
containing the located search item.
-
For example, ``lsof -V -iTCP@foobar -a -d 999'' may not report a
failure to locate open files at ``TCP@foobar'' and may not list
any, if none have a file descriptor number of 999.
A similar situation arises when HASSECURITY and HASNOSOCKSECURITY are
defined at compile time and they prevent the listing of open files.
- +|-w
-
Enables (+) or disables (-) the suppression of warning messages.
-
The
lsof
builder may choose to have warning messages disabled or enabled by
default.
The default warning message state is indicated in the output of the
-h
or
-?
option.
Disabling warning messages when they are already disabled or enabling
them when already enabled is acceptable.
-
The
-t
option selects the
-w
option.
- -x [fl]
-
This option may accompany the
+d
and
+D
options to direct their processing to cross over symbolic links
and|or file system mount points encountered when scanning the
directory (+d) or directory tree (+D).
-
If
-x
is specified by itself without a following parameter, cross-over
processing of both symbolic links and file system mount points is
enabled.
Note that when
-x
is specified without a parameter, the next argument must begin with '-'
or '+'.
-
The optional 'f' parameter enables file system mount point cross-over
processing; 'l', symbolic link cross-over processing.
-
The
-x
option may not be supplied without also supplying a
+d
or
+D
option.
- -X
-
This is a dialect-specific option.
-
AIX:
-
- This IBM AIX RISC/System 6000 option requests the reporting
of executed text file and shared library references.
-
WARNING:
because this option uses the kernel readx() function, its use on
a busy AIX system might cause an application process to hang so
completely that it can neither be killed nor stopped.
I have never seen this happen or had a report of its happening,
but I think there is a remote possibility it could happen.
-
By default use of readx() is disabled.
On AIX 5L and above
lsof
may need setuid-root permission to perform the actions this
option requests.
-
The
lsof
builder may specify that the
-X
option be restricted to processes whose real UID is root.
If that has been done, the
-X
option will not appear in the
-h
or
-?
help output unless the real UID of the
lsof
process is root.
The default
lsof
distribution allows any UID to specify
-X,
so by default it will appear in the help output.
-
When AIX readx() use
is disabled,
lsof
may not be able to report information for all text and loader file
references, but it may also avoid exacerbating an AIX
kernel directory search kernel error, known as the Stale Segment
ID bug.
-
The readx() function, used by
lsof
or any other program to access some sections of kernel virtual
memory, can trigger the Stale Segment ID bug.
It can cause the kernel's dir_search() function to believe erroneously
that part of an in-memory copy of a file system directory has been
zeroed.
Another application process, distinct from
lsof,
asking the kernel to search the directory - e.g., by using
open(2) -
can cause dir_search() to loop forever, thus hanging the application process.
-
Consult the
lsof
FAQ (The FAQ section gives its location.)
and the
00README
file of the
lsof
distribution for a more complete description of the Stale Segment ID bug,
its APAR, and methods for defining readx() use when compiling
lsof.
-
Linux:
-
- This Linux option requests that
lsof
skip the reporting of information on all open TCP, UDP and UDPLITE IPv4
and IPv6 files.
-
This Linux option is most useful when the system has an extremely
large number of open TCP, UDP and UDPLITE files, the processing of whose
information in the
/proc/net/tcp*
and
/proc/net/udp*
files would take
lsof
a long time, and whose reporting is not of interest.
-
Use this option with care and only when you are sure that the
information you want
lsof
to display isn't associated with open TCP, UDP or UDPLITE socket files.
-
Solaris 10 and above:
-
- This Solaris 10 and above option requests the reporting of cached
paths for files that have been deleted - i.e., removed with
rm(1)
or
unlink(2).
-
The cached path is followed by the string `` (deleted)'' to indicate
that the path by which the file was opened has been deleted.
-
Because intervening changes made to the path - i.e., renames with
mv(1)
or
rename(2)
- are not recorded in the cached path, what
lsof
reports is only the path by which the file was opened, not its
possibly different final path.
- -z [z]
-
specifies how Solaris 10 and higher zone information is to be handled.
-
Without a following argument - e.g., NO
z -
the option specifies that zone names are to be listed in the ZONE
output column.
-
The
-z
option may be followed by a zone name,
z.
That causes lsof to list only open files for processes in that zone.
Multiple
-z z
option and argument pairs may be specified to form a list of named zones.
Any open file of any process in any of the zones will be listed, subject
to other conditions specified by other options and arguments.
- -Z [Z]
-
specifies how SELinux security contexts are to be handled.
This option and 'Z' field output character support are inhibited
when SELinux is disabled in the running Linux kernel.
See
OUTPUT FOR OTHER PROGRAMS
for more information on the 'Z' field output character.
-
Without a following argument - e.g., NO
Z -
the option specifies that security contexts are to be listed in the
SECURITY-CONTEXT output column.
-
The
-Z
option may be followed by a wildcard security context name,
Z.
That causes lsof to list only open files for processes in that security
context.
Multiple
-Z Z
option and argument pairs may be specified to form a list of security
contexts.
Any open file of any process in any of the security contexts will be listed,
subject to other conditions specified by other options and arguments.
Note that
Z
can be A:B:C or *:B:C or A:B:* or *:*:C to match against the A:B:C context.
- --
-
The double minus sign option is a marker that signals the end of
the keyed options.
It may be used, for example, when the first file name begins with
a minus sign.
It may also be used when the absence of a value for the last keyed
option must be signified by the presence of a minus sign in the following
option and before the start of the file names.
- names
-
These are path names of specific files to list.
Symbolic links are resolved before use.
The first name may be separated from the preceding options with
the ``--'' option.
-
If a
name
is the mounted-on directory of a file system or the device of the
file system,
lsof
will list all the files open on the file system.
To be considered a file system, the
name
must match a mounted-on directory name in
mount(8)
output, or match the name of a block device associated with a mounted-on
directory name.
The
+|-f
option may be used to force
lsof
to consider a
name
a file system identifier (+f) or a simple file (-f).
-
If
name
is a path to a directory that is not the mounted-on directory name of
a file system, it is treated just as a regular file is treated - i.e.,
its listing is restricted to processes that have it open as a file or
as a process-specific directory, such as the root or current working
directory.
To request that
lsof
look for open files inside a directory name, use the
+d s
and
+D D
options.
-
If a
name
is the base name of a family of multiplexed files - e. g, AIX's
/dev/pt[cs] -
lsof
will list all the associated multiplexed files on the device that
are open - e.g.,
/dev/pt[cs]/1,
/dev/pt[cs]/2,
etc.
-
If a
name
is a UNIX domain socket name,
lsof
will usually search for it by the characters of the name alone - exactly as
it is specified and is recorded in the kernel socket structure.
(See the next paragraph for an exception to that rule for Linux.)
Specifying a relative path - e.g.,
./file
- in place of the
file's absolute path - e.g.,
/tmp/file
- won't work because
lsof
must match the characters you specify with what it finds in the
kernel UNIX domain socket structures.
-
If a
name
is a Linux UNIX domain socket name, in one case
lsof
is able to search for it by its device and inode number, allowing
name
to be a relative path.
The case requires that the absolute path -- i.e., one beginning with a
slash ('/') be used by the process that created the socket, and hence be
stored in the
/proc/net/unix
file; and it requires that
lsof
be able to obtain the device and node numbers of both the absolute path in
/proc/net/unix
and
name
via successful
stat(2)
system calls.
When those conditions are met,
lsof
will be able to search for the UNIX domain socket when some path to it is
is specified in
name.
Thus, for example, if the path is
/dev/log,
and an
lsof
search is initiated when the working directory is
/dev,
then
name
could be
./log.
-
If a
name
is none of the above,
lsof
will list any open files whose device and inode match that of the
specified path
name.
-
If you have also specified the
-b
option,
the only
names
you may safely specify are file systems for which your mount table
supplies alternate device numbers.
See the
AVOIDING KERNEL BLOCKS
and
ALTERNATE DEVICE NUMBERS
sections for more information.
-
Multiple file names are joined in a single ORed set before
participating in AND option selection.
AFS
Lsof
supports the recognition of AFS files for these dialects (and AFS
versions):
AIX 4.1.4 (AFS 3.4a)
HP-UX 9.0.5 (AFS 3.4a)
Linux 1.2.13 (AFS 3.3)
Solaris 2.[56] (AFS 3.4a)
It may recognize AFS files on other versions of these dialects,
but has not been tested there.
Depending on how AFS is implemented,
lsof
may recognize AFS files in other dialects, or may have difficulties
recognizing AFS files in the supported dialects.
Lsof
may have trouble identifying all aspects of AFS files in
supported dialects when AFS kernel support is implemented via
dynamic modules whose addresses do not appear in the kernel's
variable name list.
In that case,
lsof
may have to guess at the identity of AFS files, and might not be able to
obtain volume information from the kernel that is needed for calculating
AFS volume node numbers.
When
lsof
can't compute volume node numbers, it reports blank in the NODE column.
The
-A A
option is available in some dialect implementations of
lsof
for specifying the name list file where dynamic module kernel
addresses may be found.
When this option is available, it will be listed in the
lsof
help output, presented in response to the
-h
or
-?
See the
lsof
FAQ (The FAQ section gives its location.)
for more information about dynamic modules, their
symbols, and how they affect
lsof
options.
Because AFS path lookups don't seem to participate in the
kernel's name cache operations,
lsof
can't identify path name components for AFS files.
SECURITY
Lsof
has three features that may cause security concerns.
First, its default compilation mode allows anyone to list all
open files with it.
Second, by default it creates a user-readable and user-writable device
cache file in the home directory of the real user ID that executes
lsof.
(The list-all-open-files and device cache features may be disabled when
lsof
is compiled.)
Third, its
-k
and
-m
options name alternate kernel name list or memory files.
Restricting the listing of all open files is controlled by the
compile-time HASSECURITY and HASNOSOCKSECURITY options.
When HASSECURITY is defined,
lsof
will allow only the root user to list all open files.
The non-root user may list only open files of processes with the same user
IDentification number as the real user ID number of the
lsof
process (the one that its user logged on with).
However, if HASSECURITY and HASNOSOCKSECURITY are both defined,
anyone may list open socket files, provided they are selected
with the
-i
option.
When HASSECURITY is not defined, anyone may list all open files.
Help output, presented in response to the
-h
or
-?
option, gives the status of the HASSECURITY and HASNOSOCKSECURITY definitions.
See the
Security
section of the
00README
file of the
lsof
distribution for information on building
lsof
with the HASSECURITY and HASNOSOCKSECURITY options enabled.
Creation and use of a user-readable and user-writable device
cache file is controlled by the compile-time HASDCACHE option.
See the
DEVICE CACHE FILE
section and the sections that follow it for details on how its path
is formed.
For security considerations it is important to note that in the default
lsof
distribution, if the real user ID under which
lsof
is executed is root, the device cache file will be written in root's
home directory - e.g.,
/
or
/root.
When HASDCACHE is not defined,
lsof
does not write or attempt to read a device cache file.
When HASDCACHE is defined, the
lsof
help output, presented in response to the
-h,
-D?,
or
-?
options, will provide device cache file handling information.
When HASDCACHE is not defined, the
-h
or
-?
output will have no
-D
option description.
Before you decide to disable the device cache file feature - enabling
it improves the performance of
lsof
by reducing the startup overhead of examining all the nodes in
/dev
(or
/devices)
- read the discussion of it in the
00DCACHE
file of the
lsof
distribution and the
lsof
FAQ (The FAQ section gives its location.)
WHEN IN DOUBT, YOU CAN TEMPORARILY DISABLE THE USE OF THE DEVICE CACHE FILE
WITH THE
-Di
OPTION.
When
lsof
user declares alternate kernel name list or memory files with the
-k
and
-m
options,
lsof
checks the user's authority to read them with
access(2).
This is intended to prevent whatever special power
lsof's
modes might confer on it from letting it read files not normally
accessible via the authority of the real user ID.
OUTPUT
This section describes the information
lsof
lists for each open file.
See the
OUTPUT FOR OTHER PROGRAMS
section for additional information on output that can be processed
by another program.
Lsof
only outputs printable (declared so by
isprint(3))
8 bit characters.
Non-printable characters are printed in one of three forms:
the C ``\[bfrnt]'' form;
the control character `^' form (e.g., ``^@'');
or hexadecimal leading ``\x'' form (e.g., ``\xab'').
Space is non-printable in the COMMAND column (``\x20'')
and printable elsewhere.
For some dialects - if HASSETLOCALE is defined in the dialect's
machine.h header file -
lsof
will print the extended 8 bit characters of a language locale.
The
lsof
process must be supplied a language locale environment variable
(e.g., LANG) whose value represents a known language locale
in which the extended characters are considered printable by
isprint(3).
Otherwise
lsof
considers the extended characters non-printable and prints them according
to its rules for non-printable characters, stated above.
Consult your dialect's
setlocale(3)
man page for the names of other environment variables that may
be used in place of LANG - e.g., LC_ALL, LC_CTYPE, etc.
Lsof's
language locale support for a dialect also covers wide characters - e.g.,
UTF-8 - when HASSETLOCALE and HASWIDECHAR are defined in the dialect's
machine.h header file, and when a suitable language locale has been defined
in the appropriate environment variable for the
lsof
process.
Wide characters are printable under those conditions if
iswprint(3)
reports them to be.
If HASSETLOCALE, HASWIDECHAR and a suitable language locale aren't defined,
or if
iswprint(3)
reports wide characters that aren't printable,
lsof
considers the wide characters non-printable and prints each of their
8 bits according to its rules for non-printable characters, stated above.
Consult the answers to the "Language locale support" questions in the
lsof FAQ (The FAQ section gives its location.) for more information.
Lsof
dynamically sizes the output columns each time it runs, guaranteeing
that each column is a minimum size.
It also guarantees that each column is separated from its predecessor
by at least one space.
- COMMAND
-
contains the first nine characters of the name of the UNIX command
associated with the process.
If a non-zero
w
value is specified to the
+c w
option, the column contains the first
w
characters of the name of the UNIX command associated with the process
up to the limit of characters supplied to
lsof
by the UNIX dialect.
(See the description of the
+c w
command or the
lsof
FAQ for more information.
The FAQ section gives its location.)
-
If
w
is less than the length of the column title, ``COMMAND'', it will
be raised to that length.
-
If a zero
w
value is specified to the
+c w
option, the column contains all the characters of the name of the UNIX command
associated with the process.
-
All command name characters maintained by the kernel in its structures
are displayed in field output when the command name descriptor (`c')
is specified.
See the
OUTPUT FOR OTHER COMMANDS
section for information on selecting field output and the associated
command name descriptor.
- PID
-
is the Process IDentification number of the process.
- ZONE
-
is the Solaris 10 and higher zone name.
This column must be selected with the
-z
option.
- SECURITY-CONTEXT
-
is the SELinux security context.
This column must be selected with the
-Z
option.
Note that the
-Z
option is inhibited when SELinux is disabled in the running Linux
kernel.
- PPID
-
is the Parent Process IDentification number of the process.
It is only displayed when the
-R
option has been specified.
- PGID
-
is the process group IDentification number associated with
the process.
It is only displayed when the
-g
option has been specified.
- USER
-
is the user ID number or login name of the user to whom
the process belongs, usually the same as reported by
ps(1).
However, on Linux USER is the user ID number or login that owns
the directory in /proc where
lsof
finds information about the process.
Usually that is the same value reported by
ps(1),
but may differ when the process has changed its effective user ID.
(See the
-l
option description for information on when a user ID number or
login name is displayed.)
- FD
-
is the File Descriptor number of the file or:
-
cwd current working directory;
Lnn library references (AIX);
err FD information error (see NAME column);
jld jail directory (FreeBSD);
ltx shared library text (code and data);
Mxx hex memory-mapped type number xx.
m86 DOS Merge mapped file;
mem memory-mapped file;
mmap memory-mapped device;
pd parent directory;
rtd root directory;
tr kernel trace file (OpenBSD);
txt program text (code and data);
v86 VP/ix mapped file;
-
FD is followed by one of these characters, describing the mode under which
the file is open:
-
r for read access;
w for write access;
u for read and write access;
space if mode unknown and no lock
character follows;
`-' if mode unknown and lock
character follows.
-
The mode character is followed by one of these lock characters, describing
the type of lock applied to the file:
-
N for a Solaris NFS lock of unknown type;
r for read lock on part of the file;
R for a read lock on the entire file;
w for a write lock on part of the file;
W for a write lock on the entire file;
u for a read and write lock of any length;
U for a lock of unknown type;
x for an SCO OpenServer Xenix lock on part
of the file;
X for an SCO OpenServer Xenix lock on the
entire file;
space if there is no lock.
-
See the
LOCKS
section for more information on the lock information character.
-
The FD column contents constitutes a single field for parsing in
post-processing scripts.
- TYPE
-
is the type of the node associated with the file - e.g., GDIR, GREG,
VDIR, VREG, etc.
-
or ``IPv4'' for an IPv4 socket;
-
or ``IPv6'' for an open IPv6 network file - even if its address is
IPv4, mapped in an IPv6 address;
-
or ``ax25'' for a Linux AX.25 socket;
-
or ``inet'' for an Internet domain socket;
-
or ``lla'' for a HP-UX link level access file;
-
or ``rte'' for an AF_ROUTE socket;
-
or ``sock'' for a socket of unknown domain;
-
or ``unix'' for a UNIX domain socket;
-
or ``x.25'' for an HP-UX x.25 socket;
-
or ``BLK'' for a block special file;
-
or ``CHR'' for a character special file;
-
or ``DEL'' for a Linux map file that has been deleted;
-
or ``DIR'' for a directory;
-
or ``DOOR'' for a VDOOR file;
-
or ``FIFO'' for a FIFO special file;
-
or ``KQUEUE'' for a BSD style kernel event queue file;
-
or ``LINK'' for a symbolic link file;
-
or ``MPB'' for a multiplexed block file;
-
or ``MPC'' for a multiplexed character file;
-
or ``NOFD'' for a Linux /proc/<PID>/fd directory that can't be opened --
the directory path appears in the NAME column, followed by an error
message;
-
or ``PAS'' for a
/proc/as
file;
-
or ``PAXV'' for a
/proc/auxv
file;
-
or ``PCRE'' for a
/proc/cred
file;
-
or ``PCTL'' for a
/proc
control file;
-
or ``PCUR'' for the current
/proc
process;
-
or ``PCWD'' for a
/proc
current working directory;
-
or ``PDIR'' for a
/proc
directory;
-
or ``PETY'' for a
/proc
executable type (etype);
-
or ``PFD'' for a
/proc
file descriptor;
-
or ``PFDR'' for a
/proc
file descriptor directory;
-
or ``PFIL'' for an executable
/proc
file;
-
or ``PFPR'' for a
/proc
FP register set;
-
or ``PGD'' for a
/proc/pagedata
file;
-
or ``PGID'' for a
/proc
group notifier file;
-
or ``PIPE'' for pipes;
-
or ``PLC'' for a
/proc/lwpctl
file;
-
or ``PLDR'' for a
/proc/lpw
directory;
-
or ``PLDT'' for a
/proc/ldt
file;
-
or ``PLPI'' for a
/proc/lpsinfo
file;
-
or ``PLST'' for a
/proc/lstatus
file;
-
or ``PLU'' for a
/proc/lusage
file;
-
or ``PLWG'' for a
/proc/gwindows
file;
-
or ``PLWI'' for a
/proc/lwpsinfo
file;
-
or ``PLWS'' for a
/proc/lwpstatus
file;
-
or ``PLWU'' for a
/proc/lwpusage
file;
-
or ``PLWX'' for a
/proc/xregs
file'
-
or ``PMAP'' for a
/proc
map file (map);
-
or ``PMEM'' for a
/proc
memory image file;
-
or ``PNTF'' for a
/proc
process notifier file;
-
or ``POBJ'' for a
/proc/object
file;
-
or ``PODR'' for a
/proc/object
directory;
-
or ``POLP'' for an old format
/proc
light weight process file;
-
or ``POPF'' for an old format
/proc
PID file;
-
or ``POPG'' for an old format
/proc
page data file;
-
or ``PORT'' for a SYSV named pipe;
-
or ``PREG'' for a
/proc
register file;
-
or ``PRMP'' for a
/proc/rmap
file;
-
or ``PRTD'' for a
/proc
root directory;
-
or ``PSGA'' for a
/proc/sigact
file;
-
or ``PSIN'' for a
/proc/psinfo
file;
-
or ``PSTA'' for a
/proc
status file;
-
or ``PSXSEM'' for a POSIX semaphore file;
-
or ``PSXSHM'' for a POSIX shared memory file;
-
or ``PUSG'' for a
/proc/usage
file;
-
or ``PW'' for a
/proc/watch
file;
-
or ``PXMP'' for a
/proc/xmap
file;
-
or ``REG'' for a regular file;
-
or ``SMT'' for a shared memory transport file;
-
or ``STSO'' for a stream socket;
-
or ``UNNM'' for an unnamed type file;
-
or ``XNAM'' for an OpenServer Xenix special file of unknown type;
-
or ``XSEM'' for an OpenServer Xenix semaphore file;
-
or ``XSD'' for an OpenServer Xenix shared data file;
-
or the four type number octets if the corresponding name isn't known.
- FILE-ADDR
-
contains the kernel file structure address when
f
has been specified to
+f;
- FCT
-
contains the file reference count from the kernel file structure when
c
has been specified to
+f;
- FILE-FLAG
-
when
g
or
G
has been specified to
+f,
this field contains the contents of the f_flag[s] member of the kernel
file structure and the kernel's per-process open file flags (if available);
`G' causes them to be displayed in hexadecimal;
`g', as short-hand names;
two lists may be displayed with entries separated by commas, the
lists separated by a semicolon (`;');
the first list may contain short-hand names for f_flag[s] values from
the following table:
-
AIO asynchronous I/O (e.g., FAIO)
AP append
ASYN asynchronous I/O (e.g., FASYNC)
BAS block, test, and set in use
BKIU block if in use
BL use block offsets
BSK block seek
CA copy avoid
CIO concurrent I/O
CLON clone
CLRD CL read
CR create
DF defer
DFI defer IND
DFLU data flush
DIR direct
DLY delay
DOCL do clone
DSYN data-only integrity
DTY must be a directory
EVO event only
EX open for exec
EXCL exclusive open
FSYN synchronous writes
GCDF defer during unp_gc() (AIX)
GCMK mark during unp_gc() (AIX)
GTTY accessed via /dev/tty
HUP HUP in progress
KERN kernel
KIOC kernel-issued ioctl
LCK has lock
LG large file
MBLK stream message block
MK mark
MNT mount
MSYN multiplex synchronization
NATM don't update atime
NB non-blocking I/O
NBDR no BDRM check
NBIO SYSV non-blocking I/O
NBF n-buffering in effect
NC no cache
ND no delay
NDSY no data synchronization
NET network
NFLK don't follow links
NMFS NM file system
NOTO disable background stop
NSH no share
NTTY no controlling TTY
OLRM OLR mirror
PAIO POSIX asynchronous I/O
PP POSIX pipe
R read
RC file and record locking cache
REV revoked
RSH shared read
RSYN read synchronization
RW read and write access
SL shared lock
SNAP cooked snapshot
SOCK socket
SQSH Sequent shared set on open
SQSV Sequent SVM set on open
SQR Sequent set repair on open
SQS1 Sequent full shared open
SQS2 Sequent partial shared open
STPI stop I/O
SWR synchronous read
SYN file integrity while writing
TCPM avoid TCP collision
TR truncate
W write
WKUP parallel I/O synchronization
WTG parallel I/O synchronization
VH vhangup pending
VTXT virtual text
XL exclusive lock
-
this list of names was derived from F* #define's in dialect header files
<fcntl.h>, <linux</fs.h>, <sys/fcntl.c>, <sys/fcntlcom.h>, and <sys/file.h>;
see the lsof.h header file for a list showing the correspondence
between the above short-hand names and the header file definitions;
-
the second list (after the semicolon) may contain short-hand names
for kernel per-process open file flags from this table:
-
ALLC allocated
BR the file has been read
BHUP activity stopped by SIGHUP
BW the file has been written
CLSG closing
CX close-on-exec (see fcntl(F_SETFD))
LCK lock was applied
MP memory-mapped
OPIP open pending - in progress
RSVW reserved wait
SHMT UF_FSHMAT set (AIX)
USE in use (multi-threaded)
- NODE-ID
-
(or INODE-ADDR for some dialects)
contains a unique identifier for the file node (usually the kernel
vnode or inode address, but also occasionally a concatenation of
device and node number) when
n
has been specified to
+f;
- DEVICE
-
contains the device numbers, separated by commas, for a character special,
block special, regular, directory or NFS file;
-
or ``memory'' for a memory file system node under Tru64 UNIX;
-
or the address of the private data area of a Solaris socket
stream;
-
or a kernel reference address that identifies the file
(The kernel reference address may be used for FIFO's, for example.);
-
or
the base address or device name of a Linux AX.25 socket device.
-
Usually only the lower thirty two bits of Tru64 UNIX kernel addresses
are displayed.
- SIZE, SIZE/OFF, or OFFSET
-
is the size of the file or the file offset in bytes.
A value is displayed in this column only if it is available.
Lsof
displays whatever value - size or offset - is appropriate for the type
of the file and the version of
lsof.
-
On some UNIX dialects
lsof
can't obtain accurate or consistent file offset information from its
kernel data sources, sometimes just for particular kinds of files
(e.g., socket files.)
In other cases, files don't have true sizes - e.g., sockets, FIFOs,
pipes - so
lsof
displays for their sizes the content amounts it finds in their kernel
buffer descriptors (e.g., socket buffer size counts or TCP/IP window
sizes.)
Consult the
lsof
FAQ (The FAQ section gives its location.)
for more information.
-
The file size is displayed in decimal;
the offset is normally displayed in decimal with a leading ``0t'' if
it contains 8 digits or less; in hexadecimal with a leading ``0x'' if
it is longer than 8 digits.
(Consult the
-o o
option description for information on when 8 might default to
some other value.)
-
Thus the leading ``0t'' and ``0x'' identify an offset when the column
may contain both a size and an offset (i.e., its title is SIZE/OFF).
-
If the
-o
option is specified,
lsof
always displays the file offset (or nothing if no offset is available)
and labels the column OFFSET.
The offset always begins with ``0t'' or ``0x'' as described above.
-
The
lsof
user can control the switch from ``0t'' to ``0x'' with the
-o o
option.
Consult its description for more information.
-
If the
-s
option is specified,
lsof
always displays the file size (or nothing if no size is available)
and labels the column SIZE.
The
-o
and
-s
options are mutually exclusive; they can't both be specified.
-
For files that don't have a fixed size - e.g., don't reside
on a disk device -
lsof
will display appropriate information about the current size or
position of the file if it is available in the kernel structures
that define the file.
- NLINK
-
contains the file link count when
+L
has been specified;
- NODE
-
is the node number of a local file;
-
or the inode number of an NFS file in the server host;
-
or the Internet protocol type - e. g, ``TCP'';
-
or ``STR'' for a stream;
-
or ``CCITT'' for an HP-UX x.25 socket;
-
or the IRQ or inode number of a Linux AX.25 socket device.
- NAME
-
is the name of the mount point and file system on which the file resides;
-
or the name of a file specified in the
names
option (after any symbolic links have been resolved);
-
or the name of a character special or block special device;
-
or the local and remote Internet addresses of a network file;
the local host name or IP number is followed by a colon (':'), the
port, ``->'', and the two-part remote address;
IP addresses may be reported as numbers or names, depending on the
+|-M,
-n,
and
-P
options;
colon-separated IPv6 numbers are enclosed in square brackets;
IPv4 INADDR_ANY and IPv6 IN6_IS_ADDR_UNSPECIFIED addresses, and
zero port numbers are represented by an asterisk ('*');
a UDP destination address may be followed by the amount of time
elapsed since the last packet was sent to the destination;
TCP, UDP and UDPLITE remote addresses may be followed by TCP/TPI
information in parentheses - state (e.g., ``(ESTABLISHED)'', ``(Unbound)''),
queue sizes, and window sizes (not all dialects) - in a fashion
similar to what
netstat(1)
reports;
see the
-T
option description or the description of the TCP/TPI field in
OUTPUT FOR OTHER PROGRAMS
for more information on state, queue size, and window size;
-
or the address or name of a UNIX domain socket, possibly including
a stream clone device name, a file system object's path name, local
and foreign kernel addresses, socket pair information, and a bound
vnode address;
-
or the local and remote mount point names of an NFS file;
-
or ``STR'', followed by the stream name;
-
or a stream character device name, followed by ``->'' and the stream name
or a list of stream module names, separated by ``->'';
-
or ``STR:'' followed by the SCO OpenServer stream device and module
names, separated by ``->'';
-
or system directory name, `` -- '', and as many components of the path
name as
lsof
can find in the kernel's name cache for selected dialects
(See the
KERNEL NAME CACHE
section for more information.);
-
or ``PIPE->'', followed by a Solaris kernel pipe destination address;
-
or ``COMMON:'', followed by the vnode device information structure's
device name, for a Solaris common vnode;
-
or the address family, followed by a slash (`/'), followed by fourteen
comma-separated bytes of a non-Internet raw socket address;
-
or the HP-UX x.25 local address, followed by the virtual connection
number (if any), followed by the remote address (if any);
-
or ``(dead)'' for disassociated Tru64 UNIX files - typically terminal files
that have been flagged with the TIOCNOTTY ioctl and closed by daemons;
-
or ``rd=<offset>'' and ``wr=<offset>'' for the values of the
read and write offsets of a FIFO;
-
or ``clone n:/dev/event'' for SCO OpenServer file clones of the
/dev/event
device, where
n
is the minor device number of the file;
-
or ``(socketpair: n)'' for a Solaris 2.6, 8, 9 or 10
UNIX domain socket, created by the
socketpair(3N)
network function;
-
or ``no PCB'' for socket files that do not have a protocol block
associated with them, optionally followed by ``, CANTSENDMORE'' if
sending on the socket has been disabled, or ``, CANTRCVMORE'' if
receiving on the socket has been disabled (e.g., by the
shutdown(2)
function);
-
or the local and remote addresses of a Linux IPX socket file
in the form <net>:[<node>:]<port>, followed in parentheses
by the transmit and receive queue sizes, and the connection state;
-
or ``dgram'' or ``stream'' for the type UnixWare 7.1.1 and above in-kernel
UNIX domain sockets, followed by a colon (':') and the local path name
when available, followed by ``->'' and the remote path name or kernel
socket address in hexadecimal when available.
For dialects that support a ``namefs'' file system, allowing one
file to be attached to another with
fattach(3C),
lsof
will add ``(FA:<address1><direction><address2>)'' to the NAME column.
<address1> and <address2> are hexadecimal vnode addresses.
<direction> will be ``<-'' if <address2> has been fattach'ed to
this vnode whose address is <address1>;
and ``->'' if <address1>, the vnode address of this vnode, has been
fattach'ed to <address2>.
<address1> may be omitted if it already appears in the DEVICE column.
Lsof
may add two parenthetical notes to the NAME column for open Solaris 10 files:
``(?)'' if
lsof
considers the path name of questionable accuracy;
and ``(deleted)'' if the
-X
option has been specified and
lsof
detects the open file's path name has been deleted.
Consult the
lsof
FAQ (The FAQ section gives its location.)
for more information on these NAME column additions.
LOCKS
Lsof
can't adequately report the wide variety of UNIX dialect file locks
in a single character.
What it reports in a single character is a compromise between the
information it finds in the kernel and the limitations of the reporting
format.
Moreover, when a process holds several byte level locks on a file,
lsof
only reports the status of the first lock it encounters.
If it is a byte level lock, then the lock character will be reported
in lower case - i.e., `r', `w', or `x' - rather than the upper case
equivalent reported for a full file lock.
Generally
lsof
can only report on locks held by local processes on local files.
When a local process sets a lock on a remotely mounted (e.g., NFS)
file, the remote server host usually records the lock state.
One exception is Solaris - at some patch levels of 2.3, and in all
versions above 2.4, the Solaris kernel records information on remote
locks in local structures.
Lsof
has trouble reporting locks for some UNIX dialects.
Consult the
BUGS
section of this manual page or the
lsof
FAQ (The FAQ section gives its location.)
for more information.
OUTPUT FOR OTHER PROGRAMS
When the
-F
option is specified,
lsof
produces output that is suitable for processing by another program - e.g, an
awk
or
Perl
script, or a C program.
Each unit of information is output in a field that is identified
with a leading character and terminated by a NL (012) (or a NUL
(000) if the 0 (zero) field identifier character is specified.)
The data of the field follows immediately after the field identification
character and extends to the field terminator.
It is possible to think of field output as process and file sets.
A process set begins with a field whose identifier is `p' (for
process IDentifier (PID)).
It extends to the beginning of the next PID field or the beginning
of the first file set of the process, whichever comes first.
Included in the process set are fields that identify the command,
the process group IDentification (PGID) number, and the user ID (UID)
number or login name.
A file set begins with a field whose identifier is `f' (for
file descriptor).
It is followed by lines that describe the file's access mode,
lock state, type, device, size, offset, inode, protocol, name
and stream module names.
It extends to the beginning of the next file or process set,
whichever comes first.
When the NUL (000) field terminator has been selected with the
0 (zero) field identifier character,
lsof
ends each process and file set with a NL (012) character.
Lsof
always produces one field, the PID (`p') field.
All other fields may be declared optionally in the field identifier
character list that follows the
-F
option.
When a field selection character identifies an item
lsof
does not normally list - e.g., PPID, selected with
-R -
specification of the field character - e.g., ``-FR'' -
also selects the listing of the item.
It is entirely possible to select a set of fields that cannot
easily be parsed - e.g., if the field descriptor field is not
selected, it may be difficult to identify file sets.
To help you avoid this difficulty,
lsof
supports the
-F
option; it selects the output of all fields with NL terminators
(the
-F0
option pair selects the output of all fields with NUL terminators).
For compatibility reasons neither
-F
nor
-F0
select the raw device field.
These are the fields that
lsof
will produce.
The single character listed first is the field identifier.
a file access mode
c process command name (all characters from proc or
user structure)
C file structure share count
d file's device character code
D file's major/minor device number (0x<hexadecimal>)
f file descriptor
F file structure address (0x<hexadecimal>)
G file flaGs (0x<hexadecimal>; names if +fg follows)
i file's inode number
k link count
l file's lock status
L process login name
m marker between repeated output
n file name, comment, Internet address
N node identifier (ox<hexadecimal>
o file's offset (decimal)
p process ID (always selected)
g process group ID
P protocol name
r raw device number (0x<hexadecimal>)
R parent process ID
s file's size (decimal)
S file's stream identification
t file's type
T TCP/TPI information, identified by prefixes (the
`=' is part of the prefix):
QR=<read queue size>
QS=<send queue size>
SO=<socket options and values> (not all dialects)
SS=<socket states> (not all dialects)
ST=<connection state>
TF=<TCP flags and values> (not all dialects)
WR=<window read size> (not all dialects)
WW=<window write size> (not all dialects)
(TCP/TPI information isn't reported for all supported
UNIX dialects. The -h or -? help output for the
-T option will show what TCP/TPI reporting can be
requested.)
u process user ID
z Solaris 10 and higher zone name
Z SELinux security context (inhibited when SELinux is disabled)
0 use NUL field terminator character in place of NL
1-9 dialect-specific field identifiers (The output
of -F? identifies the information to be found
in dialect-specific fields.)
You can get on-line help information on these characters and their
descriptions by specifying the
-F?
option pair.
(Escape the `?' character as your shell requires.)
Additional information on field content can be found in the
OUTPUT
section.
As an example, ``-F pcfn'' will select the process ID (`p'),
command name (`c'), file descriptor (`f') and file name (`n')
fields with an NL field terminator character; ``-F pcfn0''
selects the same output with a NUL (000) field terminator character.
Lsof
doesn't produce all fields for every process or file set, only
those that are available.
Some fields are mutually exclusive: file device characters and
file major/minor device numbers; file inode number and protocol
name; file name and stream identification; file size and offset.
One or the other member of these mutually exclusive sets will appear
in field output, but not both.
Normally
lsof
ends each field with a NL (012) character.
The
0 (zero) field identifier character may be specified to change the
field terminator character
to a NUL (000).
A NUL terminator may be easier to process with
xargs (1),
for example, or with programs whose quoting mechanisms may not
easily cope with the range of characters in the field output.
When the NUL field terminator is in use,
lsof
ends each process and file set with a NL (012).
Three aids to producing programs that can process
lsof
field output are included in the
lsof
distribution.
The first is a C header file,
lsof_fields.h,
that contains symbols for the field identification characters, indexes for
storing them in a table, and explanation strings that may be compiled into
programs.
Lsof
uses this header file.
The second aid is a set of sample scripts that process field output,
written in
awk,
Perl
4, and
Perl
5.
They're located in the
scripts
subdirectory of the
lsof
distribution.
The third aid is the C library used for the
lsof
test suite.
The test suite is written in C and uses field output to validate
the correct operation of
lsof.
The library can be found in the
tests/LTlib.c
file of the
lsof
distribution.
The library uses the first aid, the
lsof_fields.h
header file.
BLOCKS AND TIMEOUTS
Lsof
can be blocked by some kernel functions that it uses -
lstat(2),
readlink(2),
and
stat(2).
These functions are stalled in the kernel, for example, when the
hosts where mounted NFS file systems reside become inaccessible.
Lsof
attempts to break these blocks with timers and child processes,
but the techniques are not wholly reliable.
When
lsof
does manage to break a block, it will report the break with an error
message.
The messages may be suppressed with the
-t
and
-w
options.
The default timeout value may be displayed with the
-h
or
-?
option, and it may be changed with the
-S [t]
option.
The minimum for
t
is two seconds, but you should avoid small values, since slow system
responsiveness can cause short timeouts to expire unexpectedly and
perhaps stop
lsof
before it can produce any output.
When
lsof
has to break a block during its access of mounted file system
information, it normally continues, although with less information
available to display about open files.
Lsof
can also be directed to avoid the protection of timers and child processes
when using the kernel functions that might block by specifying the
-O
option.
While this will allow
lsof
to start up with less overhead, it exposes
lsof
completely to the kernel situations that might block it.
Use this option cautiously.
AVOIDING KERNEL BLOCKS
You can use the
-b
option to tell
lsof
to avoid using kernel functions that would block.
Some cautions apply.
First, using this option usually requires that your system supply
alternate device numbers in place of the device numbers that
lsof
would normally obtain with the
lstat(2)
and
stat(2)
kernel functions.
See the
ALTERNATE DEVICE NUMBERS
section for more information on alternate device numbers.
Second, you can't specify
names
for
lsof
to locate unless they're file system names.
This is because
lsof
needs to know the device and inode numbers of files listed with
names
in the
lsof
options, and the
-b
option prevents
lsof
from obtaining them.
Moreover, since
lsof
only has device numbers for the file systems that have alternates,
its ability to locate files on file systems depends completely on the
availability and accuracy of the alternates.
If no alternates are available, or if they're incorrect,
lsof
won't be able to locate files on the named file systems.
Third, if the names of your file system directories that
lsof
obtains from your system's mount table are symbolic links,
lsof
won't be able to resolve the links.
This is because the
-b
option causes
lsof
to avoid the kernel
readlink(2)
function it uses to resolve symbolic links.
Finally, using the
-b
option causes
lsof
to issue warning messages when it needs to use the kernel functions
that the
-b
option directs it to avoid.
You can suppress these messages by specifying the
-w
option, but if you do, you won't see the alternate device numbers
reported in the warning messages.
ALTERNATE DEVICE NUMBERS
On some dialects, when
lsof
has to break a block because it can't get information about a
mounted file system via the
lstat(2)
and
stat(2)
kernel functions, or because you specified the
-b
option,
lsof
can obtain some of the information it needs - the device number and
possibly the file system type - from the system mount table.
When that is possible,
lsof
will report the device number it obtained.
(You can suppress the report by specifying the
-w
option.)
You can assist this process if your mount table is supported with an
/etc/mtab
or
/etc/mnttab
file that contains an options field by adding a ``dev=xxxx'' field for
mount points that do not have one in their options strings.
Note: you must be able to edit the file - i.e., some mount tables
like recent Solaris /etc/mnttab or Linux /proc/mounts are read-only
and can't be modified.
You may also be able to supply device numbers using the
+m
and
+m m
options, provided they are supported by your dialect.
Check the output of
lsof's
-h
or
-?
options to see if the
+m
and
+m m
options are available.
The ``xxxx'' portion of the field is the hexadecimal value
of the file system's device number.
(Consult the
st_dev
field of the output of the
lstat(2)
and
stat(2)
functions for the appropriate values for your file systems.)
Here's an example from a Sun Solaris 2.6
/etc/mnttab
for a file system remotely mounted via NFS:
nfs ignore,noquota,dev=2a40001
There's an advantage to having ``dev=xxxx'' entries in your mount
table file, especially for file systems that are mounted from remote
NFS servers.
When a remote server crashes and you want to identify its users by running
lsof
on one of its clients,
lsof
probably won't be able to get output from the
lstat(2)
and
stat(2)
functions for the file system.
If it can obtain the file system's device number from the mount table,
it will be able to display the files open on the crashed NFS server.
Some dialects that do not use an ASCII
/etc/mtab
or
/etc/mnttab
file for the mount table may still provide an alternative device number
in their internal mount tables.
This includes AIX, Apple Darwin, FreeBSD, NetBSD, OpenBSD, and Tru64 UNIX.
Lsof
knows how to obtain the alternative device number for these dialects
and uses it when its attempt to
lstat(2)
or
stat(2)
the file system is blocked.
If you're not sure your dialect supplies alternate device numbers
for file systems from its mount table, use this
lsof
incantation to see if it reports any alternate device numbers:
-
lsof -b
Look for standard error file warning messages that
begin ``assuming "dev=xxxx" from ...''.
KERNEL NAME CACHE
Lsof
is able to examine the kernel's name cache or use other kernel
facilities (e.g., the ADVFS 4.x tag_to_path() function under
Tru64 UNIX) on some dialects for most file system types,
excluding AFS, and extract recently used path name components from it.
(AFS file system path lookups don't use the kernel's name cache; some
Solaris VxFS file system operations apparently don't use it, either.)
Lsof
reports the complete paths it finds in the NAME column.
If
lsof
can't report all components in a path, it reports in the NAME column
the file system name, followed by a space, two `-' characters, another
space, and the name components it has located, separated by
the `/' character.
When
lsof
is run in repeat mode - i.e., with the
-r
option specified - the extent to which it can report path name
components for the same file may vary from cycle to cycle.
That's because other running processes can cause the kernel to
remove entries from its name cache and replace them with others.
Lsof's
use of the kernel name cache to identify the paths of files
can lead it to report incorrect components under some circumstances.
This can happen when the kernel name cache uses device and node
number as a key (e.g., SCO OpenServer) and a key on a rapidly
changing file system is reused.
If the UNIX dialect's kernel doesn't purge the name cache entry for
a file when it is unlinked,
lsof
may find a reference to the wrong entry in the cache.
The
lsof
FAQ (The FAQ section gives its location.)
has more information on this situation.
Lsof
can report path name components for these dialects:
FreeBSD
HP-UX
Linux
NetBSD
NEXTSTEP
OpenBSD
OPENSTEP
SCO OpenServer
SCO|Caldera UnixWare
Solaris
Tru64 UNIX
Lsof
can't report path name components for these dialects:
AIX
If you want to know why
lsof
can't report path name components for some dialects, see the
lsof
FAQ (The FAQ section gives its location.)
DEVICE CACHE FILE
Examining all members of the
/dev
(or
/devices)
node tree with
stat(2)
functions can be time consuming.
What's more, the information that
lsof
needs - device number, inode number, and path - rarely changes.
Consequently,
lsof
normally maintains an ASCII text file of cached
/dev
(or
/devices)
information (exception: the /proc-based Linux
lsof
where it's not needed.)
The local system administrator who builds
lsof
can control the way the device cache file path is formed, selecting
from these options:
Path from the -D option;
Path from an environment variable;
System-wide path;
Personal path (the default);
Personal path, modified by an environment variable.
Consult the output of the
-h,
-D? ,
or
-?
help options for the current state of device cache support.
The help output lists the default read-mode device cache file path that
is in effect for the current invocation of
lsof.
The
-D?
option output lists the read-only and write device cache file paths,
the names of any applicable environment variables, and the personal
device cache path format.
Lsof
can detect that the current device cache file has been accidentally
or maliciously modified by integrity checks, including the computation
and verification of a sixteen bit Cyclic Redundancy Check (CRC) sum on
the file's contents.
When
lsof
senses something wrong with the file, it issues a warning and attempts
to remove the current cache file and create a new copy, but only to
a path that the process can legitimately write.
The path from which a
lsof
process may attempt to read a device cache file may not be the same
as the path to which it can legitimately write.
Thus when
lsof
senses that it needs to update the device cache file, it may
choose a different path for writing it from the path from which
it read an incorrect or outdated version.
If available, the
-Dr
option will inhibit the writing of a new device cache file.
(It's always available when specified without a path name argument.)
When a new device is added to the system, the device cache file may
need to be recreated.
Since
lsof
compares the mtime of the device cache file with the mtime and ctime
of the
/dev
(or
/devices)
directory, it usually detects that a new device has been added;
in that case
lsof
issues a warning message and attempts to rebuild the device cache file.
Whenever
lsof
writes a device cache file, it sets its ownership to the real UID
of the executing process, and its permission modes to 0600, this
restricting its reading and writing to the file's owner.
LSOF PERMISSIONS THAT AFFECT DEVICE CACHE FILE ACCESS
Two permissions of the
lsof
executable affect its ability to access device cache files.
The permissions are set by the local system administrator when
lsof
is installed.
The first and rarer permission is setuid-root.
It comes into effect when
lsof
is executed; its effective UID is then
root, while its real (i.e., that of the logged-on user) UID is not.
The
lsof
distribution recommends that versions for these dialects run setuid-root.
HP-UX 11.11 and 11.23
Linux
The second and more common permission is setgid.
It comes into effect when the effective group IDentification number (GID)
of the
lsof
process is set to one that can access kernel memory devices -
e.g., ``kmem'', ``sys'', or ``system''.
An
lsof
process that has setgid permission usually surrenders the permission
after it has accessed the kernel memory devices.
When it does that,
lsof
can allow more liberal device cache path formations.
The
lsof
distribution recommends that versions for these dialects run setgid
and be allowed to surrender setgid permission.
AIX 5.[12] and 5.3-ML1
Apple Darwin 7.x Power Macintosh systems
FreeBSD 4.x, 4.1x, 5.x and [67].x for x86-based systems
FreeBSD 5.x and [67].x for Alpha, AMD64 and Sparc64-based
systems
HP-UX 11.00
NetBSD 1.[456], 2.x and 3.x for Alpha, x86, and SPARC-based
systems
NEXTSTEP 3.[13] for NEXTSTEP architectures
OpenBSD 2.[89] and 3.[0-9] for x86-based systems
OPENSTEP 4.x
SCO OpenServer Release 5.0.6 for x86-based systems
SCO|Caldera UnixWare 7.1.4 for x86-based systems
Solaris 2.6, 8, 9 and 10
Tru64 UNIX 5.1
(Note:
lsof
for AIX 5L and above needs setuid-root permission if its
-X
option is used.)
Lsof
for these dialects does not support a device cache, so the permissions
given to the executable don't apply to the device cache file.
Linux
DEVICE CACHE FILE PATH FROM THE -D OPTION
The
-D
option provides limited means for specifying the device cache file path.
Its
?
function will report the read-only and write device cache file paths that
lsof
will use.
When the
-D
b,
r,
and
u
functions are available, you can use them to request that the cache file be
built in a specific location (b[path]);
read but not rebuilt (r[path]);
or read and rebuilt (u[path]).
The
b,
r,
and
u
functions are restricted under some conditions.
They are restricted when the
lsof
process is setuid-root.
The path specified with the
r
function is always read-only, even
when it is available.
The
b,
r,
and
u
functions are also restricted when the
lsof
process runs setgid and
lsof
doesn't surrender the setgid permission.
(See the
LSOF PERMISSIONS THAT AFFECT DEVICE CACHE FILE ACCESS
section for a list of implementations that normally don't surrender
their setgid permission.)
A further
-D
function,
i
(for ignore), is always available.
When available, the
b
function tells
lsof
to read device information from the kernel with the
stat(2)
function and build a device cache file at the indicated path.
When available, the
r
function tells
lsof
to read the device cache file, but not update it.
When a path argument accompanies
-Dr,
it names the device cache file path.
The
r
function is always available when it is specified without a
path name argument.
If
lsof
is not running setuid-root and surrenders its setgid permission,
a path name argument may accompany the
r
function.
When available, the
u
function tells
lsof
to attempt to read and use the device cache file.
If it can't read the file, or if it finds the contents of the
file incorrect or outdated, it will read information from the kernel,
and attempt to write an updated version of the device cache file,
but only to a path it considers legitimate for the
lsof
process effective and real UIDs.
DEVICE CACHE PATH FROM AN ENVIRONMENT VARIABLE
Lsof's
second choice for the device cache file is the contents of the
LSOFDEVCACHE environment variable.
It avoids this choice if the
lsof
process is setuid-root, or the real UID of the process is root.
A further restriction applies to a device cache file path taken from
the LSOFDEVCACHE environment variable:
lsof
will not write a device cache file to the path if the
lsof
process doesn't surrender its setgid permission.
(See the
LSOF PERMISSIONS THAT AFFECT DEVICE CACHE FILE ACCESS
section for information on implementations that don't surrender
their setgid permission.)
The local system administrator can disable the use of the LSOFDEVCACHE
environment variable or change its name when building
lsof.
Consult the output of
-D?
for the environment variable's name.
SYSTEM-WIDE DEVICE CACHE PATH
The local system administrator may choose to have a system-wide
device cache file when building
lsof.
That file will generally be constructed by a special system administration
procedure when the system is booted or when the contents of
/dev
or
/devices)
changes.
If defined, it is
lsof's
third device cache file path choice.
You can tell that a system-wide device cache file is in effect
for your local installation by examining the
lsof
help option output - i.e., the output from the
-h
or
-?
option.
Lsof
will never write to the system-wide device cache file path by
default.
It must be explicitly named with a
-D
function in a root-owned procedure.
Once the file has been written, the procedure must change its permission
modes to 0644 (owner-read and owner-write, group-read, and other-read).
PERSONAL DEVICE CACHE PATH (DEFAULT)
The default device cache file path of the
lsof
distribution is one recorded in the home directory of the real UID
that executes
lsof.
Added to the home directory is a second path component of the form
.lsof_hostname.
This is
lsof's
fourth device cache file path choice, and is
usually the default.
If a system-wide device cache file path was defined when
lsof
was built,
this fourth choice will be applied when
lsof
can't find the system-wide device cache file.
This is the
only
time
lsof
uses two paths when reading the device cache file.
The
hostname
part of the second component is the base
name of the executing host, as returned by
gethostname(2).
The base name is defined to be the characters preceding the first `.'
in the
gethostname(2)
output, or all the
gethostname(2)
output if it contains no `.'.
The device cache file belongs to the user ID and is readable and
writable by the user ID alone - i.e., its modes are 0600.
Each distinct real user ID on a given host that executes
lsof
has a distinct device cache file.
The
hostname
part of the path distinguishes device cache files in an NFS-mounted
home directory into which device cache files are written from
several different hosts.
The personal device cache file path formed by this method represents
a device cache file that
lsof
will attempt to read, and will attempt to write should it not
exist or should its contents be incorrect or outdated.
The
-Dr
option without a path name argument will inhibit the writing of a new
device cache file.
The
-D?
option will list the format specification for constructing the
personal device cache file.
The conversions used in the format specification are described in the
00DCACHE
file of the
lsof
distribution.
MODIFIED PERSONAL DEVICE CACHE PATH
If this option is defined by the local system administrator when
lsof
is built, the LSOFPERSDCPATH environment variable contents may
be used to add a component of the personal device cache file path.
The LSOFPERSDCPATH variable contents are inserted in the path at the
place marked by the local system administrator with the ``%p''
conversion in the HASPERSDC format specification of the dialect's
machine.h
header file.
(It's placed right after the home directory in the default
lsof
distribution.)
Thus, for example, if LSOFPERSDCPATH contains ``LSOF'', the home
directory is ``/Homes/abe'', the host name is ``lsof.itap.purdue.edu'',
and the HASPERSDC format is the default (``%h/%p.lsof_%L''), the
modified personal device cache file path is:
/Homes/abe/LSOF/.lsof_vic
The LSOFPERSDCPATH environment variable is ignored when the
lsof
process is setuid-root or when the real UID of the process is root.
Lsof
will not write to a modified personal device cache file path if the
lsof
process doesn't surrender setgid permission.
(See the
LSOF PERMISSIONS THAT AFFECT DEVICE CACHE FILE ACCESS
section for a list of implementations that normally don't surrender
their setgid permission.)
If, for example, you want to create a sub-directory of personal
device cache file paths by using the LSOFPERSDCPATH environment
variable to name it, and
lsof
doesn't surrender its setgid permission, you will have to allow
lsof
to create device cache files at the standard personal path and
move them to your subdirectory with shell commands.
The local system administrator may: disable this option when
lsof
is built; change the name of the environment variable from
LSOFPERSDCPATH to something else; change the HASPERSDC
format to include the personal path component in another place;
or exclude the personal path component entirely.
Consult the output of the
-D?
option for the environment variable's name and the HASPERSDC
format specification.
DIAGNOSTICS
Errors are identified with messages on the standard error file.
Lsof
returns a one (1) if any error was detected, including the failure to
locate command names, file names, Internet addresses or files, login
names, NFS files, PIDs, PGIDs, or UIDs it was asked to list.
If the
-V
option is specified,
lsof
will indicate the search items it failed to list.
It returns a zero (0) if no errors were detected and if it was able to
list some information about all the specified search arguments.
When
lsof
cannot open access to
/dev
(or
/devices)
or one of its subdirectories, or get information on a file in them with
stat(2),
it issues a warning message and continues.
That
lsof
will issue warning messages about inaccessible files in
/dev
(or
/devices)
is indicated in its help output - requested with the
-h
or
>B -?
options - with the message:
Inaccessible /dev warnings are enabled.
The warning message may be suppressed with the
-w
option.
It may also have been suppressed by the system administrator when
lsof
was compiled by the setting of the WARNDEVACCESS definition.
In this case, the output from the help options will include the message:
Inaccessible /dev warnings are disabled.
Inaccessible device warning messages usually disappear after
lsof
has created a working device cache file.
EXAMPLES
For a more extensive set of examples, documented more fully, see the
00QUICKSTART
file of the
lsof
distribution.
To list all open files, use:
-
lsof
To list all open Internet, x.25 (HP-UX), and UNIX domain files, use:
-
lsof -i -U
To list all open IPv4 network files in use by the process whose PID is
1234, use:
-
lsof -i 4 -a -p 1234
Presuming the UNIX dialect supports IPv6, to list only open IPv6
network files, use:
-
lsof -i 6
To list all files using any protocol on ports 513, 514, or 515 of host
wonderland.cc.purdue.edu, use:
-
lsof -i @wonderland.cc.purdue.edu:513-515
To list all files using any protocol on any port of mace.cc.purdue.edu
(cc.purdue.edu is the default domain), use:
-
lsof -i @mace
To list all open files for login name ``abe'', or user ID 1234, or
process 456, or process 123, or process 789, use:
-
lsof -p 456,123,789 -u 1234,abe
To list all open files on device /dev/hd4, use:
-
lsof /dev/hd4
To find the process that has /u/abe/foo open, use:
-
lsof /u/abe/foo
To send a SIGHUP to the processes that have /u/abe/bar open, use:
-
kill -HUP `lsof -t /u/abe/bar`
To find any open file, including an open UNIX domain socket file,
with the name
/dev/log,
use:
-
lsof /dev/log
To find processes with open files on the NFS file system named
/nfs/mount/point
whose server is inaccessible, and presuming your mount table supplies
the device number for
/nfs/mount/point,
use:
-
lsof -b /nfs/mount/point
To do the preceding search with warning messages suppressed, use:
-
lsof -bw /nfs/mount/point
To ignore the device cache file, use:
-
lsof -Di
To obtain PID and command name field output for each process, file
descriptor, file device number, and file inode number for each file
of each process, use:
-
lsof -FpcfDi
To list the files at descriptors 1 and 3 of every process running the
lsof
command for login ID ``abe'' every 10 seconds, use:
-
lsof -c lsof -a -d 1 -d 3 -u abe -r10
To list the current working directory of processes running a command that
is exactly four characters long and has an 'o' or 'O' in character three,
use this regular expression form of the
-c c
option:
-
lsof -c /^..o.$/i -a -d cwd
To find an IP version 4 socket file by its associated numeric dot-form
address, use:
-
lsof -i@128.210.15.17
To find an IP version 6 socket file (when the UNIX dialect supports
IPv6) by its associated numeric colon-form address, use:
-
lsof -i@[0:1:2:3:4:5:6:7]
To find an IP version 6 socket file (when the UNIX dialect supports
IPv6) by an associated numeric colon-form address that has a run of
zeroes in it - e.g., the loop-back address - use:
-
lsof -i@[::1]
To obtain a repeat mode marker line that contains the current time, use:
-
lsof -rm====%T====
To add spaces to the previous marker line, use:
-
lsof -r "m==== %T ===="
BUGS
Since
lsof
reads kernel memory in its search for open files, rapid changes in kernel
memory may produce unpredictable results.
When a file has multiple record locks, the lock status character
(following the file descriptor) is derived from a test of the first
lock structure, not from any combination of the individual record
locks that might be described by multiple lock structures.
Lsof
can't search for files with restrictive access permissions by
name
unless it is installed with root set-UID permission.
Otherwise it is limited to searching for files to which its user
or its set-GID group (if any) has access permission.
The display of the destination address of a raw socket (e.g., for
ping)
depends on the UNIX operating system.
Some dialects store the destination address in the raw socket's protocol
control block, some do not.
Lsof
can't always represent Solaris device numbers in the same way that
ls(1)
does.
For example, the major and minor device numbers that the
lstat(2)
and
stat(2)
functions report for the directory on which CD-ROM files are mounted
(typically
/cdrom)
are not the same as the ones that it reports for the device on which
CD-ROM files are mounted (typically
/dev/sr0).
(Lsof reports the directory numbers.)
The support for
/proc
file systems is available only for BSD and Tru64 UNIX dialects, Linux, and
dialects derived from SYSV R4 - e.g., FreeBSD, NetBSD, OpenBSD, Solaris,
UnixWare.
Some
/proc
file items - device number, inode number, and file size -
are unavailable in some dialects.
Searching for files in a
/proc
file system may require that the full path name be specified.
No text (txt) file descriptors are displayed for Linux
processes.
All entries for files other than the current working directory,
the root directory, and numerical file descriptors are labeled
mem
descriptors.
Lsof
can't search for Tru64 UNIX named pipes by name, because their kernel
implementation of lstat(2) returns an improper device number for a
named pipe.
Lsof
can't report fully or correctly on HP-UX 9.01, 10.20, and 11.00 locks
because of insufficient access to kernel data or errors in the
kernel data.
See the
lsof
FAQ (The FAQ section gives its location.)
for details.
The AIX SMT file type is a fabrication.
It's made up for file structures whose type (15) isn't defined in the AIX
/usr/include/sys/file.h
header file.
One way to create such file structures is to run X clients with the DISPLAY
variable set to ``:0.0''.
The
+|-f[cfgGn]
option is not supported under /proc-based Linux
lsof,
because it doesn't read kernel structures from kernel memory.
ENVIRONMENT
Lsof
may access these environment variables.
- LANG
-
defines a language locale.
See
setlocale(3)
for the names of other variables that can be used in place
of LANG - e.g., LC_ALL, LC_TYPE, etc.
- LSOFDEVCACHE
-
defines the path to a device cache file.
See the
DEVICE CACHE PATH FROM AN ENVIRONMENT VARIABLE
section for more information.
- LSOFPERSDCPATH
-
defines the middle component of a modified personal device cache
file path.
See the
MODIFIED PERSONAL DEVICE CACHE PATH
section for more information.
FAQ
Frequently-asked questions and their answers (an FAQ) are
available in the
00FAQ
file of the
lsof
distribution.
That file is also available via anonymous ftp from
lsof.itap.purdue.edu
at
pub/tools/unix/lsofFAQ.
The URL is:
-
ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof/FAQ
FILES
- /dev/kmem
-
kernel virtual memory device
- /dev/mem
-
physical memory device
- /dev/swap
-
system paging device
- .lsof_hostname
-
lsof's
device cache file
(The suffix,
hostname,
is the first component of the host's name returned by
gethostname(2).)
AUTHORS
Lsof
was written by Victor A. Abell <abe@purdue.edu> of Purdue University.
Many others have contributed to
lsof.
They're listed in the
00CREDITS
file of the
lsof
distribution.
DISTRIBUTION
The latest distribution of
lsof
is available via anonymous ftp from the host
lsof.itap.purdue.edu.
You'll find the
lsof
distribution in the
pub/tools/unix/lsof
directory.
You can also use this URL:
-
ftp://lsof.itap.purdue.edu/pub/tools/unix/lsof
Lsof
is also mirrored elsewhere.
When you access
lsof.itap.purdue.edu
and change to its
pub/tools/unix/lsof
directory, you'll be given a list of some mirror sites.
The
pub/tools/unix/lsof
directory also contains a more complete list in its
mirrors
file.
Use mirrors with caution - not all mirrors always have the latest
lsof
revision.
Some pre-compiled
Lsof
executables are available on
lsof.itap.purdue.edu,
but their use is discouraged - it's better that you build
your own from the sources.
If you feel you must use a pre-compiled executable, please
read the cautions that appear in the README files of the
pub/tools/unix/lsof/binaries
subdirectories and in the 00* files of the distribution.
More information on the
lsof
distribution can be found in its
README.lsof_<version>
file.
If you intend to get the
lsof
distribution and build it, please read
README.lsof_<version>
and the other 00* files of the distribution before sending questions
to the author.
SEE ALSO
Not all the following manual pages may exist in every UNIX
dialect to which
lsof
has been ported.
access(2),
awk(1),
crash(1),
fattach(3C),
ff(1),
fstat(8),
fuser(1),
gethostname(2),
isprint(3),
kill(1),
localtime(3),
lstat(2),
modload(8),
mount(8),
netstat(1),
ofiles(8L),
perl(1),
ps(1),
readlink(2),
setlocale(3),
stat(2),
strftime(3),
time(2),
uname(1).
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- OPTIONS
-
- AFS
-
- SECURITY
-
- OUTPUT
-
- LOCKS
-
- OUTPUT FOR OTHER PROGRAMS
-
- BLOCKS AND TIMEOUTS
-
- AVOIDING KERNEL BLOCKS
-
- ALTERNATE DEVICE NUMBERS
-
- KERNEL NAME CACHE
-
- DEVICE CACHE FILE
-
- LSOF PERMISSIONS THAT AFFECT DEVICE CACHE FILE ACCESS
-
- DEVICE CACHE FILE PATH FROM THE -D OPTION
-
- DEVICE CACHE PATH FROM AN ENVIRONMENT VARIABLE
-
- SYSTEM-WIDE DEVICE CACHE PATH
-
- PERSONAL DEVICE CACHE PATH (DEFAULT)
-
- MODIFIED PERSONAL DEVICE CACHE PATH
-
- DIAGNOSTICS
-
- EXAMPLES
-
- BUGS
-
- ENVIRONMENT
-
- FAQ
-
- FILES
-
- AUTHORS
-
- DISTRIBUTION
-
- SEE ALSO
-
This document was created by
man2html,
using the manual pages.
Time: 07:35:45 GMT, March 26, 2013