illumos: manual page: fuser.8

FUSER(8) Maintenance Commands and Procedures FUSER(8)

NAME

fuser - identify users of files and devices

SYNOPSIS

DESCRIPTION

The fuser utility displays the process IDs of the processes that are
using the files specified as arguments.

Each process ID is followed by a letter code. These letter codes are
interpreted as follows. If the process is using the file as

c
Indicates that the process is using the file as its current
directory.

m
Indicates that the process is using a file mapped with mmap(2). See
mmap(2) for details.

n
Indicates that the process is holding a non-blocking mandatory lock
on the file.

o
Indicates that the process is using the file as an open file.

r
Indicates that the process is using the file as its root directory.

t
Indicates that the process is using the file as its text file.

y
Indicates that the process is using the file as its controlling
terminal.

For block special devices with mounted file systems, all processes using
any file on that device are listed. For all types of files (text files,
executables, directories, devices, and so forth), only the processes
using that file are reported.

For all types of devices, fuser also displays any known kernel consumers
that have the device open. Kernel consumers are displayed in one of the
following formats:

[module_name]
[module_name,dev_path=path]
[module_name,dev=(major,minor)]
[module_name,dev=(major,minor),dev_path=path]

If more than one group of files are specified, the options may be
respecified for each additional group of files. A lone dash cancels the
options currently in force.

The process IDs are printed as a single line on the standard output,
separated by spaces and terminated with a single new line. All other
output is written on standard error.

Any user can run fuser, but only the superuser can terminate another
user's process.

OPTIONS

The following options are supported:

-c
Reports on files that are mount points for file systems, and
any files within that mounted file system.

-d
Report device usage information for all minor nodes bound to
the same device node as the specified minor node. This option
does not report file usage for files within a mounted file
system.

-f
Prints a report for the named file, not for files within a
mounted file system.

-k
Sends the SIGKILL signal to each process. Since this option
spawns kills for each process, the kill messages may not show
up immediately (see kill(2)). No signals will be sent to kernel
file consumers.

-n
Lists only processes with non-blocking mandatory locks on a
file.

-s sig
Sends a signal to each process. The sig option argument
specifies one of the symbolic names defined in the <signal.h>
header, or a decimal integer signal number. If sig is a
symbolic name, it is recognized in a case-independent fashion,
without the SIG prefix. The -k option is equivalent to -s KILL
or -s 9. No signals will be sent to kernel file consumers.

-u
Displays the user login name in parentheses following the
process ID.

EXAMPLES

Example 1: Reporting on the Mount Point and Files

The following example reports on the mount point and files within the
mounted file system.

example% fuser -c /export/foo

Example 2: Restricting Output when Reporting on the Mount Point and Files

The following example reports on the mount point and files within the
mounted file system, but the output is restricted to processes that hold
non-blocking mandatory locks.

example% fuser -cn /export/foo

Example 3: Sending SIGTERM to Processes Holding a Non-blocking Mandatory

Lock

The following command sends SIGTERM to any processes that hold a non-
blocking mandatory lock on file /export/foo/my_file.

example% fuser -fn -s term /export/foo/my_file

ENVIRONMENT VARIABLES

See environ(7) for descriptions of the following environment variables
that affect the execution of fuser: LANG, LC_ALL LC_CTYPE, LC_MESSAGES,
and NLSPATH.

ATTRIBUTES

NOTES

Because fuser works with a snapshot of the system image, it may miss
processes that begin using a file while fuser is running. Also, processes
reported as using a file may have stopped using it while fuser was
running. These factors should discourage the use of the -k option.

October 21, 2003 FUSER(8)