# lsof(8) - man - phpman > **TLDR:** List open files and the corresponding processes. > - Find the processes that have a given file open: `lsof {{path/to/file}}` - Find the process that opened a local internet port: `lsof -i :{{port}}` - Only output the process ID (PID): `lsof -t {{path/to/file}}` - List files opened by the given user: `lsof -u {{username}}` - List files opened by the given command or process: `lsof -c {{process_or_command_name}}` - List files opened by a specific process, given its PID: `lsof -p {{pid}}` - List open files in a directory: `lsof +D {{path/to/directory}}` - Find the process that is listening on a local IPv6 TCP port and don't convert network or port numbers: `lsof -i6TCP:{{port}} -sTCP:LISTEN -n -P` *Source: tldr-pages* --- [LSOF(8)](https://www.chedong.com/phpMan.php/man/LSOF/8/markdown) System Manager's Manual [LSOF(8)](https://www.chedong.com/phpMan.php/man/LSOF/8/markdown) ## NAME lsof - list open files ## SYNOPSIS **lsof** [ **-?abChlnNOPRtUvVX** ] [ **-A** _A_ ] [ **-c** _c_ ] [ **+c** _c_ ] [ **+|-d** _d_ ] [ **+|-D** _D_ ] [ **+|-e** _s_ ] [ **+|-E** ] [ **+|-f** **[cfgGn]** ] [ **-F** _[f]_ ] [ **-g** _[s]_ ] [ **-i** _[i]_ ] [ **-k** _k_ ] [ **-K** _k_ ] [ **+|-L** _[l]_ ] [ **+|-m** _m_ ] [ **+|-M** ] [ **-o** _[o]_ ] [ **-p** _s_ ] [ **+|-r** _[t[m]]_ ] [ **-s** _[p:s]_ ] [ **-S** _[t]_ ] [ **-T** _[t]_ ] [ **-u** _s_ ] [ **+|-w** ] [ **-x** _[fl]_ ] [ **-z** _[z]_ ] [ **-Z** _[Z]_ ] [ **--** ] [_names_] ## DESCRIPTION _Lsof_ revision 4.93.2 lists on its standard output file information about files opened by pro‐ cesses for the following UNIX dialects: Apple Darwin 9 and Mac OS X 10.[567] FreeBSD 8.[234], 9.0 and 1[012].0 for AMD64-based systems Linux 2.1.72 and above for x86-based systems Solaris 9, 10 and 11 (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 pro‐ grams. 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 inter‐ rupt or quit signal. See the **+|-r** _[t[m]]_ 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 un‐ less **-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 **-u**foo option produces a listing of all network files OR files be‐ longing 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 be‐ fore any other selection criteria are applied. The **-a** option may be used to AND the selections. For example, specifying **-a**, **-U**, and **-u**foo 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 selec‐ tion 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 -i -a -u ther 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 -abC -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 ambigu‐ ity is possible, start a new option with a `-' character - e.g., ``**-F** **-n**''. If the next op‐ tion 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 re‐ quest 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 `?' charac‐ ter as your shell requires.) ### -a ### -A 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 mod‐ ules, their symbols, and how they affect _lsof_. ### -b [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown). See the **BLOCKS** **AND** **TIMEOUTS** and **AVOIDING** **KERNEL** **BLOCKS** sections for information on using this option. ### -c 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 in‐ terpreted 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 ba‐ sic 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_ 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 See the **KERNEL** **NAME** **CACHE** section for more information. **+d** _s_ causes _lsof_ to search for all open instances of directory _s_ and the files and direc‐ tories it contains at its top level. **+d** 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)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) function. ### -d 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 participat‐ ing in AND option selection. When there are exclusion and inclusion members in the set, _lsof_ reports them as er‐ rors 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_ 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)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) function. Further note: _lsof_ may process this option slowly and require a large amount of dy‐ namic memory to do it. This is because it must descend the entire directory tree, rooted at _D_, calling [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) 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 di‐ rectory _D_ is large, these steps can take a long time, so use this option prudently. ### -D 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 fol‐ lowed 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** sec‐ tion 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 de‐ vice cache file, the names of any environment variables whose values _lsof_ will exam‐ ine 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)](https://www.chedong.com/phpMan.php/man/gethostname/2/markdown). 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 de‐ fault 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. **+|-e** _s_ exempts the file system whose path name is _s_ from being subjected to kernel function calls that might block. The **+e** option exempts [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown), [_lstat_(2)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown) and most _read__‐ [_link_(2)](https://www.chedong.com/phpMan.php/man/link/2/markdown) kernel function calls. The **-e** option exempts only [_stat(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown)_ and [_lstat_(2)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown) ker‐ nel function calls. Multiple file systems may be specified with separate **+|-e** spec‐ ifications and each may have [_readlink_(2)](https://www.chedong.com/phpMan.php/man/readlink/2/markdown) calls exempted or not. This option is currently implemented only for Linux. **CAUTION:** this option can easily be mis-applied to other than the file system of in‐ terest, because it uses path name rather than the more reliable device and inode numbers. (Device and inode numbers are acquired via the potentially blocking [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) kernel call and are thus not available, but see the **+|-m** _m_ option as a pos‐ sible alternative way to supply device numbers.) **Use** **this** **option** **with** **great** **care** **and** **fully** **specify** **the** **path** **name** **of** **the** **file** **system** **to** **be** **exempted.** When open files on exempted file systems are reported, it may not be possible to ob‐ tain all their information. Therefore, some information columns will be blank, the characters ``UNKN'' preface the values in the TYPE column, and the applicable exemp‐ tion option is added in parentheses to the end of the NAME column. (Some device number information might be made available via the **+|-m** _m_ option.) **+|-E** **+E** specifies that Linux pipe, Linux UNIX socket and Linux pseudoterminal files should be displayed with endpoint information and the files of the endpoints should also be displayed. Note: UNIX socket file endpoint information is only available when the compile flags line of **-v** output contains HASUXSOCKEPT, and psudoterminal endpoint information is only available when the compile flags line contains HASP‐ TYEPT. Pipe endpoint information is displayed in the NAME column in the form ``_PID,cmd,FD__‐ _mode_'', where _PID_ is the endpoint process ID; _cmd_ is the endpoint process command; _FD_ is the endpoint file's descriptor; and _mode_ is the endpoint file's access mode. Pseudoterminal endpoint information is displayed in the NAME column as ``->/dev/pts_min_ _PID,cmd,FDmode_'' or ``_PID,cmd,FDmode_''. The first form is for a master device; the second, for a slave device. _min_ is a slave device's minor device number; and _PID,_ _cmd,_ _FD_ and _mode_ are the same as with pipe endpoint information. Note: psudoterminal endpoint information is only available when the compile flags line of **-V** output contains HASPTYEPT. UNIX socket file endpoint information is displayed in the NAME column in the form ``type=_TYPE_ ->INO=_INODE_ _PID,cmd,FDmode_'', where _TYPE_ is the socket type; _INODE_ is the i-node number of the connected socket; and _PID,_ _cmd,_ _FD_ and _mode_ are the same as with pipe endpoint information. Note: UNIX socket file endpoint information is available only when the compile flags line of **-v** output contains HASUXSOCKEPT. Multiple occurrences of this information can appear in a file's NAME column. **-E** specfies that Linux pipe and Linux UNIX socket files should be displayed with endpoint information, but not the files of the endpoints. ### +|-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)](https://www.chedong.com/phpMan.php/man/mount/8/markdown), 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 parame‐ ter. 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 indi‐ cated values. File structure addresses, use counts, flags, and node addresses may be used to de‐ tect 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 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 de‐ faults 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 out‐ put 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 rea‐ sons) 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 termi‐ nator 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** sec‐ tion. 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 `?' charac‐ ter as your shell requires.) ### -g 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 with‐ out a PGID set that's all it does. ### -i ified in _i_. If no address is specified, this option selects the listing of all In‐ ternet and x.25 (HP-UX) network files. If **-i**_4_ or **-i**_6_ 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 **-i**4, followed by **-i**6 is the same as specifying **-i**, and vice-versa. Specifying **-i**4, or **-i**6 after **-i** is the same as specifying **-i**4 or **-i**6 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 op‐ tional.): [_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 di‐ alect supports IPv6, run _lsof_ and specify the **-h** or **-?** (help) option. If the dis‐ played description of the **-i** option contains ``[46]'' and ``IPv[46]'', IPv6 is sup‐ ported. IPv4 host names and addresses may not be specified if network file selection is lim‐ ited to IPv6 with **-i** 6. IPv6 host names and addresses may not be specified if net‐ work 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_, _hostname_, _hostaddr_, or _service_ - must be supplied. The `@' character, leading the host specification, is always re‐ quired; 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](https://www.chedong.com/phpMan.php/perldoc/1ebc%3A%3A1/markdown)]:1234 - Internet IPv6 host address 3ffe:[1ebc::1](https://www.chedong.com/phpMan.php/perldoc/1ebc%3A%3A1/markdown), port 1234 UDP:who - UDP who service port :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 reporting is supported. (If help output - i.e., the output of the **-h** or **-?** options - shows this option, then task (thread) reporting is supported by the dialect.) If **-K** is followed by a value, _k_, it must be ``i''. That causes _lsof_ to ignore tasks, particularly in the default, list-everything case when no other options are specified. When **-K** and **-a** are both specified on Linux, and the tasks of a main process are se‐ lected by other options, the main process will also be listed as though it were a task, but without a task ID. (See the description of the TID column in the **OUTPUT** section.) Where the FreeBSD version supports threads, all threads will be listed with their IDs. In general threads and tasks inherit the files of the caller, but may close some and open others, so _lsof_ always reports all the open files of threads and tasks. ### -k -k available under AIX on the IBM RISC/System 6000. ### -l login name lookup is working improperly or slowly. **+|-L** _[l]_ 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 num‐ ber 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** __'' 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_ specifies an alternate kernel memory file or activates mount table supplement pro‐ cessing. 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, con‐ taining 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)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) or [_lstat_(2)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown). 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 avail‐ able. **+|-M** Enables (**+**) or disables (**-**) the reporting of portmapper registrations for local TCP, UDP and UDPLITE ports, where port mapping is supported. (See the last paragraph of this option description for information about where portmapper registration report‐ ing is supported.) The default reporting mode is set by the _lsof_ builder with the HASPMAPENABLED #de‐ fine in the dialect's machine.h header file; _lsof_ is distributed with the HASPMAPEN‐ ABLED #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 en‐ abled, _lsof_ displays the portmapper registration (if any) for local TCP, UDP or UD‐ PLITE 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 UD‐ PLITE port local if: it is found in the local part of its containing kernel struc‐ ture; 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 differ‐ ent interface from the local one. See the _lsof_ FAQ (The **FAQ** section gives its location.) for further discussion of portmapper registration reporting issues. Portmapper registration reporting is supported only on dialects that have RPC header files. (Some Linux distributions with GlibC 2.14 do not have them.) When portmap‐ per registration reporting is supported, the **-h** or **-?** help output will show the **+|-M** option. ### -n hibiting conversion may make _lsof_ run faster. It is also useful when host name lookup is not working properly. ### -N ### -o 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, some‐ times 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 offset before the form is switched to ``0x...''. An _o_ value of zero (unlimited) di‐ rects _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. **-o** _o_ 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 out‐ put of the **-h** or **-?** option to determine the default that is in effect. ### -O operations - i.e., doing them in forked child processes. See the **BLOCKS** **AND** **TIME**‐‐ **OUTS** 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 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 the conversion may make _lsof_ run a little faster. It is also useful when port name lookup is not working properly. **+|-r** _[t[m]]_ 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 in‐ terrupt 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" argument specifies a format for the marker line. The characters following `m' are interpreted as a format specification to the _strf__‐ [_time_(3)](https://www.chedong.com/phpMan.php/man/time/3/markdown) function, when both it and the [_localtime_(3)](https://www.chedong.com/phpMan.php/man/localtime/3/markdown) function are available in the dialect's C library. Consult the [_strftime_(3)](https://www.chedong.com/phpMan.php/man/strftime/3/markdown) documentation for what may appear in its format specification. Note that when field output is requested with the **-F** op‐ tion, cannot contain the NL format, ``%n''. Note also that when con‐ tains spaces or other characters that affect the shell's interpretation of argu‐ ments, 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 descrip‐ tion) and a supervising _awk_ or _Perl_ script, or a C program. ### -R ### -s put column title to be changed to SIZE. If the file does not have a size, nothing is displayed. The optional **-s** _p:s_ form is available only for selected dialects, and only when the **-h** or **-?** help output lists it. When the optional form is available, the **s** may be 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 `^'. Dialects that support this option may support only one protocol. When an unsup‐ ported protocol is specified, a message will be displayed indicating state names for the protocol are unavailable. 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 will 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 re‐ quired. If only TCP and UDP files are to be listed, as controlled by the specified exclu‐ sions and inclusions, the **-i** option must be specified, too. If only a single proto‐ col'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 appro‐ priate 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 [_link_(2)](https://www.chedong.com/phpMan.php/man/link/2/markdown), and [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) - 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 following the network addresses. In normal output the information appears in paren‐ theses, each item except TCP or TPI state name identified by a keyword, followed by `=', separated from others by a single space: QR= QS= SO= SS= TF= WR= WW= 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** op‐ tion 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 selec‐ tion characters - the displaying of state is disabled by default, and it must be ex‐ plicitly selected again in the characters following **-T**. (In effect, then, the de‐ fault 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 com‐ monly appear after SO_, so_, SS_, TCP_ and TF_ in the dialect's header files - most often , and . 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 loca‐ tion.) ### -t header - e.g., so that the output may be piped to [_kill_(1)](https://www.chedong.com/phpMan.php/man/kill/1/markdown). **-t** selects the **-w** op‐ tion. ### -u 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 par‐ ticipating 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 lo‐ gin 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 belong‐ ing to root processes, specify ``-u^root'' or ``-u^0''. ### -U ### -v 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_ bi‐ nary; and system information, typically the output of _uname_'s **-a** option. ### -V 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 con‐ taining 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 **-?** op‐ tion. Disabling warning messages when they are already disabled or enabling them when already enabled is acceptable. The **-t** option selects the **-w** option. ### -x bolic 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 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 happen‐ ing, 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 se‐ tuid-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 ker‐ nel'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)](https://www.chedong.com/phpMan.php/man/open/2/markdown) - 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 re‐ porting 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)](https://www.chedong.com/phpMan.php/man/rm/1/markdown) or [_unlink_(2)](https://www.chedong.com/phpMan.php/man/unlink/2/markdown). 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)](https://www.chedong.com/phpMan.php/man/mv/1/markdown) or [_rename_(2)](https://www.chedong.com/phpMan.php/man/rename/2/markdown) - 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 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 ar‐ guments. ### -Z character support are inhibited when SELinux is disabled in the running Linux ker‐ nel. 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 con‐ texts 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 sig‐ nified 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 ``--'' op‐ tion. 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)](https://www.chedong.com/phpMan.php/man/mount/8/markdown) 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 re‐ stricted to processes that have it open as a file or as a process-specific direc‐ tory, 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 char‐ acters 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)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) 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 op‐ tion 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 ker‐ nel'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 calcu‐ lating 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 HASSECU‐ RITY 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 fol‐ low 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 perfor‐ mance of _lsof_ by reducing the startup overhead of examining all the nodes in _/dev_ (or _/de__‐ _vices_) - 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** OP‐ TION. When _lsof_ user declares alternate kernel name list or memory files with the **-k** and **-m** op‐ tions, _lsof_ checks the user's authority to read them with [_access_(2)](https://www.chedong.com/phpMan.php/man/access/2/markdown). 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)](https://www.chedong.com/phpMan.php/man/isprint/3/markdown)) 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 sup‐ plied a language locale environment variable (e.g., LANG) whose value represents a known lan‐ guage locale in which the extended characters are considered printable by [_isprint_(3)](https://www.chedong.com/phpMan.php/man/isprint/3/markdown). Other‐ wise _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)](https://www.chedong.com/phpMan.php/man/setlocale/3/markdown) 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)](https://www.chedong.com/phpMan.php/man/iswprint/3/markdown) reports them to be. If HASSETLOCALE, HASWIDECHAR and a suitable language locale aren't defined, or if [_iswprint_(3)](https://www.chedong.com/phpMan.php/man/iswprint/3/markdown) reports wide characters that aren't printable, _lsof_ considers the wide charac‐ ters 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** sec‐ tion 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 dis‐ played 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. TID is the task (thread) IDentification number, if task (thread) reporting is sup‐ ported by the dialect and a task (thread) is being listed. (If help output - i.e., the output of the **-h** or **-?** options - shows this option, then task (thread) reporting is supported by the dialect.) A blank TID column in Linux indicates a process - i.e., a non-task. TASKCMD is the task command name. Generally this will be the same as the process named in the COMMAND column, but some task implementations (e.g., Linux) permit a task to change its command name. The TASKCMD column width is subject to the same size limitation as the COMMAND column. 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, usu‐ ally the same as reported by [_ps_(1)](https://www.chedong.com/phpMan.php/man/ps/1/markdown). 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)](https://www.chedong.com/phpMan.php/man/ps/1/markdown), 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; **L**_nn_ 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//fd directory that can't be opened -- the di‐ rectory 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 ``PTS'' for a _/dev/pts_ 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 , , , , and ; 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 ad‐ dress 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 dis‐ played. 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 infor‐ mation 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., sock‐ ets, 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 win‐ dow 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 lead‐ ing ``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 mutu‐ ally 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 re‐ mote 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 in‐ formation in parentheses - state (e.g., ``(ESTABLISHED)'', ``(Unbound)''), queue sizes, and window sizes (not all dialects) - in a fashion similar to what _net__‐ [_stat_(1)](https://www.chedong.com/phpMan.php/man/stat/1/markdown) 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, sepa‐ rated 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-sepa‐ rated 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='' and ``wr='' for the values of the read and write off‐ sets 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)](https://www.chedong.com/phpMan.php/man/socketpair/3N/markdown) 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)](https://www.chedong.com/phpMan.php/man/shutdown/2/markdown) function); or the local and remote addresses of a Linux IPX socket file in the form :[:], 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 hexadeci‐ mal when available; or the association value, association index, endpoint value, local address, local port, remote address and remote port for Linux SCTP sockets; or ``protocol: '' followed by the Linux socket's protocol attribute. For dialects that support a ``namefs'' file system, allowing one file to be attached to an‐ other with [_fattach_(3C)](https://www.chedong.com/phpMan.php/man/fattach/3C/markdown), _lsof_ will add ``(FA:)'' to the NAME column. and are hexadecimal vnode addresses. will be ``<-'' if has been fattach'ed to this vnode whose address is ; and ``->'' if , the vnode address of this vnode, has been fattach'ed to . 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 addi‐ tions. ## LOCKS _Lsof_ can't adequately report the wide variety of UNIX dialect file locks in a single charac‐ ter. 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 sta‐ tus 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 equiva‐ lent 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 struc‐ tures. _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 an‐ other 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 speci‐ fied.) 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, the task (thread) ID (TID), and the user ID (UID) number or lo‐ gin 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 op‐ tionally in the field identifier character list that follows the **-F** option. When a field se‐ lection character identifies an item _lsof_ does not normally list - e.g., PPID, selected with ### -R -FR 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 termina‐ tors). 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) f file descriptor (always selected) F file structure address (0x) G file flaGs (0x; names if **+fg** follows) g process group ID i file's inode number K tasK ID k link count l file's lock status L process login name m marker between repeated output M the task comMand name n file name, comment, Internet address N node identifier (ox o file's offset (decimal) p process ID (always selected) P protocol name r raw device number (0x) 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= QS= SO= (not all dialects) SS= (not all dialects) ST= TF= (not all dialects) WR= (not all dialects) WW= (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 infor‐ mation 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 de‐ scriptor (`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 num‐ bers; 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 out‐ put, but not both. Normally _lsof_ ends each field with a NL (012) character. The 0 (zero) field identifier char‐ acter may be specified to change the field terminator character to a NUL (000). A NUL termi‐ nator may be easier to process with _xargs_ [_(1)](https://www.chedong.com/phpMan.php/man//1/markdown),_ 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)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown), [_readlink_(2)](https://www.chedong.com/phpMan.php/man/readlink/2/markdown), and [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown). 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 nor‐ mally 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)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown) and [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) 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 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)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown) and [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) kernel functions, or because you specified the **-b** option, _lsof_ can obtain some of the information it needs - the device number and pos‐ sibly 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** op‐ tion.) 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 num‐ ber. (Consult the _st_dev_ field of the output of the [_lstat_(2)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown) and [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) 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)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown) and [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) 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)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown) or [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) 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 AD‐ VFS 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 appar‐ ently don't use it, either.) _Lsof_ reports the complete paths it finds in the NAME column. If _lsof_ can't report all compo‐ nents 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 be‐ cause 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 in‐ correct 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)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) 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_) infor‐ mation (exception: the /proc-based Linux _lsof_ where it's not needed.) The local system ad‐ ministrator who builds _lsof_ can control the way the device cache file path is formed, select‐ ing 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 ef‐ fect 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 modi‐ fied 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 al‐ ways 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 exe‐ cuting 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 ac‐ cessed 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 [6789].x for x86-based systems FreeBSD 5.x, [6789].x and 1[012].8for 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 exe‐ cutable 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 **?** func‐ tion 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)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) 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 environ‐ ment 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 envi‐ ronment 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 per‐ mission.) 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 vari‐ able's name. ## SYSTEM-WIDE DEVICE CACHE PATH The local system administrator may choose to have a system-wide device cache file when build‐ ing _lsof_. That file will generally be constructed by a special system administration proce‐ dure when the system is booted or when the contents of _/dev_ or _/devices_) changes. If de‐ fined, 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 ex‐ plicitly 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 di‐ rectory 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 sys‐ tem-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)](https://www.chedong.com/phpMan.php/man/gethostname/2/markdown). The base name is defined to be the characters preceding the first `.' in the [_gethostname_(2)](https://www.chedong.com/phpMan.php/man/gethostname/2/markdown) output, or all the [_gethostname_(2)](https://www.chedong.com/phpMan.php/man/gethostname/2/markdown) 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 con‐ tents 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 LSOFPERS‐ DCPATH 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 lo‐ cal 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 de‐ fault _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 set‐ gid permission, you will have to allow _lsof_ to create device cache files at the standard per‐ sonal 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 for‐ mat 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 in‐ formation on a file in them with [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown), 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 defi‐ nition. 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 de‐ vice 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.pur‐ due.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 descrip‐ tor) is derived from a test of the first lock structure, not from any combination of the in‐ dividual 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 in‐ stalled 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)](https://www.chedong.com/phpMan.php/man/ls/1/markdown) does. For ex‐ ample, the major and minor device numbers that the [_lstat_(2)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown) and [_stat_(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown) 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)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown) 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 insuf‐ ficient access to kernel data or errors in the kernel data. See the _lsof_ FAQ (The **FAQ** sec‐ tion 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**_[cfn]_ 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)](https://www.chedong.com/phpMan.php/man/setlocale/3/markdown) for the names of other vari‐ ables 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/lsof_FAQ_._ 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)](https://www.chedong.com/phpMan.php/man/gethostname/2/markdown).) ## AUTHORS _Lsof_ was written by Victor A.Abell <> 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.pur__‐ _due.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__ file. If you intend to get the _lsof_ distribution and build it, please read _README.lsof__ 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)](https://www.chedong.com/phpMan.php/man/access/2/markdown), [awk(1)](https://www.chedong.com/phpMan.php/man/awk/1/markdown), [crash(1)](https://www.chedong.com/phpMan.php/man/crash/1/markdown), [fattach(3C)](https://www.chedong.com/phpMan.php/man/fattach/3C/markdown), [ff(1)](https://www.chedong.com/phpMan.php/man/ff/1/markdown), [fstat(8)](https://www.chedong.com/phpMan.php/man/fstat/8/markdown), [fuser(1)](https://www.chedong.com/phpMan.php/man/fuser/1/markdown), [gethostname(2)](https://www.chedong.com/phpMan.php/man/gethostname/2/markdown), is‐ [print(3)](https://www.chedong.com/phpMan.php/man/print/3/markdown), [kill(1)](https://www.chedong.com/phpMan.php/man/kill/1/markdown), [localtime(3)](https://www.chedong.com/phpMan.php/man/localtime/3/markdown), [lstat(2)](https://www.chedong.com/phpMan.php/man/lstat/2/markdown), [modload(8)](https://www.chedong.com/phpMan.php/man/modload/8/markdown), [mount(8)](https://www.chedong.com/phpMan.php/man/mount/8/markdown), [netstat(1)](https://www.chedong.com/phpMan.php/man/netstat/1/markdown), [ofiles(8L)](https://www.chedong.com/phpMan.php/man/ofiles/8L/markdown), [perl(1)](https://www.chedong.com/phpMan.php/man/perl/1/markdown), [ps(1)](https://www.chedong.com/phpMan.php/man/ps/1/markdown), [readlink(2)](https://www.chedong.com/phpMan.php/man/readlink/2/markdown), [setlocale(3)](https://www.chedong.com/phpMan.php/man/setlocale/3/markdown), [stat(2)](https://www.chedong.com/phpMan.php/man/stat/2/markdown), [strftime(3)](https://www.chedong.com/phpMan.php/man/strftime/3/markdown), [time(2)](https://www.chedong.com/phpMan.php/man/time/2/markdown), [uname(1)](https://www.chedong.com/phpMan.php/man/uname/1/markdown). Revision-4.93.2 [LSOF(8)](https://www.chedong.com/phpMan.php/man/LSOF/8/markdown)