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FSTAT(1)                    General Commands Manual                   FSTAT(1)

     fstat - display status of open files

     fstat [-AfnOv] [-M core] [-N system] [-p pid] [-u user] [file ...]

     fstat identifies open files.  A file is considered open by a process if
     it was explicitly opened, is the working directory, root directory,
     active pure text, or kernel trace file for that process.  If no options
     are specified, fstat reports on all open files in the system.


     -A          Add an output column with the address of the kernel object
                 (vnode or file), that can be matched with pstat(8) output.

     -f          Restrict examination to files open in the same file systems
                 as the named file arguments, or to the file system containing
                 the current directory if there are no additional filename
                 arguments.  For example, to find all files open in the file
                 system where the directory /var/log resides, type "fstat -f
                 /var/log".  Please see the BUGS section for issues with this

     -M core     Extract values associated with the name list from the
                 specified core instead of the default /dev/kmem.

     -N system   Extract the name list from the specified system instead of
                 the default /netbsd.

     -n          Numerical format.  Print the device number (maj,min) of the
                 file system the file resides in rather than the mount point
                 name; for special files, print the device number that the
                 special device refers to rather than the filename in /dev;
                 and print the mode of the file in octal instead of symbolic

     -O          Report file offsets instead of sizes.

     -p process  Report all files open by the specified process.

     -u user     Report all files open by the specified user.

     -v          Verbose mode.  Print error messages upon failures to locate
                 particular system data structures rather than silently
                 ignoring them.  Most of these data structures are dynamically
                 created or deleted and it is possible for them to disappear
                 while fstat is running.  This is normal and unavoidable since
                 the rest of the system is running while fstat itself is

     file ...    Restrict reports to the specified files.

     The following fields are printed:

     USER   The username of the owner of the process (effective UID).

     CMD    The command name of the process.

     PID    The process ID.

     FD     The file number in the per-process open file table or one of the
            following special names:

                  text   pure text inode
                  wd     current working directory
                  root   root inode
                  tr     kernel trace file

            If the file number is followed by an asterisk ("*"), the file is
            not an inode, but rather a socket, FIFO, or there is an error.  In
            this case the remainder of the line doesn't correspond to the
            remaining headers -- the format of the line is described later
            under SOCKETS.

     MOUNT  If the -n flag wasn't specified, this header is present and is the
            pathname that the file system the file resides in is mounted on.

     DEV    If the -n flag is specified, this header is present and is the
            major/minor number of the device that this file resides in.

     INUM   The inode number of the file.

     MODE   The mode of the file.  If the -n flag isn't specified, the mode is
            printed using a symbolic format (see strmode(3)); otherwise, the
            mode is printed as an octal number.

     SZ|DV or OFFS
            If the file is not a character or block special file, prints the
            size of the file in bytes (or the offset if the -O is specified).
            Otherwise, if the -n flag is not specified, prints the name of the
            special file as located in /dev.  If that cannot be located, or
            the -n flag is specified, prints the major/minor device number
            that the special device refers to.

     R/W    This column describes the access mode that the file allows.  The
            letter "r" indicates open for reading; the letter "w" indicates
            open for writing.  This field is useful when trying to find the
            processes that are preventing a file system from being downgraded
            to read-only.

     NAME   If filename arguments are specified and the -f flag is not, then
            this field is present and is the name associated with the given
            file.  Normally the name cannot be determined since there is no
            mapping from an open file back to the directory entry that was
            used to open that file.  Also, since different directory entries
            may reference the same file (via ln(1)), the name printed may not
            be the actual name that the process originally used to open that

     The formatting of open sockets depends on the protocol domain.  In all
     cases the first field is the domain name and the second field is the
     socket type (stream, dgram, etc.).  The remaining fields are protocol
     dependent.  For TCP, it is the address of the tcpcb, and for UDP, the
     inpcb (socket pcb).  For UNIX domain sockets, its the address of the
     socket pcb and the name of the file if available.  Otherwise the address
     of the connected pcb is printed (if connected).  For other domains, the
     protocol number and address of the socket itself are printed.  The
     attempt is to make enough information available to permit further
     analysis without duplicating netstat(1).

     For example, the addresses mentioned above are the addresses which the
     "netstat -A" command would print for TCP, UDP, and UNIX domain.  For
     kernels compiled with PIPE_SOCKETPAIR pipes appear as connected UNIX
     domain stream sockets.  A unidirectional UNIX domain socket indicates the
     direction of flow with an arrow ("<-" or "->"), and a full duplex socket
     shows a double arrow ("<->").

     For internet sockets fstat also attempts to print the internet address
     and port for the local end of a connection.  If the socket is connected,
     it also prints the remote internet address and port.  An asterisk ("*")
     is used to indicate an INADDR_ANY binding.

     netstat(1), nfsstat(1), ps(1), sockstat(1), systat(1), vmstat(1),
     fstat(2), iostat(8), pstat(8)

     The fstat command appeared in 4.3BSD-Tahoe.

     Since fstat takes a snapshot of the system, it is only correct for a very
     short period of time.

     Moreover, because DNS resolution and YP lookups cause many file
     descriptor changes, fstat does not attempt to translate the internet
     address and port numbers into symbolic names.

     Note that the -f option will not list UNIX domain sockets open in the
     file system, because the pathnames in the sockets may not be absolute and
     are not deterministic.  To find all the UNIX domain sockets, use fstat to
     list all the sockets, and look for the ones that maybe belong in the file

NetBSD 10.99                   September 6, 2019                  NetBSD 10.99