display status of open files
user] [file ...]
TABLE OF CONTENTS
identifies open files. A file is considered open
by a process if it was explicitly opened, is the working directory, root
directory, active executable text, or kernel trace file for that process. If
no options are specified,
reports on all open
files in the system.
The options are as follows:
- 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
/usr/src resides, type
# fstat -f /usr/src
- Extract values associated with the name list from the specified core
instead of the running kernel.
- Extract the name list from the specified system instead of the running
- 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. Also, print the mode of the file
in octal instead of symbolic form.
- Output file offset. Follow the size field with the descriptor's offset.
Useful for checking progress as a process works through a large file. This
information is only visible to the user or superuser.
- Report all files open by the specified process.
- Report per file io statistics in two additional columns
‘XFERS’ and ‘KBYTES’. This information is only
visible to the user or superuser.
- Report all files open by the specified user.
- 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 running.
- file ...
- Restrict reports to the specified files.
The following fields are printed:
- The username of the owner of the process (effective UID).
- The command name of the process.
- The process ID.
- The file number in the per-process open file table or one of the following
text - executable 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, 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
- If the
-n flag wasn't specified, this header is
present and is the pathname that the file system the file resides in is
- If the
-n flag is specified, this header is
present and is the major/minor number of the device that this file resides
- The inode number of the file.
- The mode of the file. If the
-n flag isn't
specified, the mode is printed using a symbolic format (see
the mode is printed as an octal number.
- 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
- If the file is not a character or block special file, prints the size of
the file in bytes. 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.
- If filename arguments are specified and the
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 file.
- Displays number of total data transfers performed on the file.
- Displays total number of Kbytes written and read to the file.
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
-domain sockets, it's the address of the socket
pcb and the address of the connected pcb (if connected). Otherwise the
protocol number and address of the socket itself are printed. The attempt is
to make enough information available to permit further analysis without
For example, the addresses mentioned above are the addresses which
netstat -A command would print for TCP, UDP, and
UNIX-domain. A unidirectional
UNIX-domain socket indicates the direction of flow
with an arrow (“<-” or “->”), and a full
duplex socket shows a double arrow (“<->”).
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. A ‘
*’ is used to
INADDR_ANY binding. In this case, the
use of the arrow (“<--” or “-->”)
indicates the direction the socket connection was created.
If the socket has been spliced to or from another socket (c.f.
a thick arrow (“<==>”, “<==”, or
“==>”), followed by the address and endpoint information of
the other socket in the splice, if available.
Every pipe is printed as an address which is the same for both sides of the pipe
and a state that is built of the letters “RWE”. W - The pipe
blocks waiting for the reader to read data. R - The pipe blocks waiting for
the writer to write data. E - The pipe is in EOF state.
device is printed
with only the kernel address of the device private data.
is printed with
some information as to queue length. Since these things are normally serviced
quickly, it is likely that nothing of real importance can be discerned.
printed with only the kernel address of the device private data.
command appeared in
Sockets in use by the kernel, such as those opened by
, will not be seen by
, even though they appear in
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
fstat does not attempt to
translate the internet address and port numbers into symbolic names.