xref: /openbsd/usr.bin/fstat/fstat.1 (revision 09467b48)
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30.\"     from: @(#)fstat.1	8.3 (Berkeley) 2/25/94
31.\"
32.Dd $Mdocdate: March 31 2019 $
33.Dt FSTAT 1
34.Os
35.Sh NAME
36.Nm fstat
37.Nd display status of open files
38.Sh SYNOPSIS
39.Nm fstat
40.Op Fl fnosv
41.Op Fl M Ar core
42.Op Fl N Ar system
43.Op Fl p Ar pid
44.Op Fl u Ar user
45.Op Ar
46.Sh DESCRIPTION
47.Nm
48identifies open files.
49A file is considered open by a process if it was explicitly opened,
50is the working directory, root directory, active executable text, or kernel
51trace file for that process.
52If no options are specified,
53.Nm
54reports on all open files in the system.
55.Pp
56The options are as follows:
57.Bl -tag -width Ds
58.It Fl f
59Restrict examination to files open in the same file systems as
60the named file arguments, or to the file system containing the
61current directory if there are no additional filename arguments.
62For example, to find all files open in the file system where the
63directory
64.Pa /usr/src
65resides, type
66.Pp
67.Dl # fstat -f /usr/src
68.It Fl M Ar core
69Extract values associated with the name list from the specified core
70instead of the running kernel.
71.It Fl N Ar system
72Extract the name list from the specified system instead of the running kernel.
73.It Fl n
74Numerical format.
75Print the device number (maj,min) of the file system
76the file resides in rather than the mount point name.
77For special files, print the
78device number that the special device refers to rather than the filename
79in
80.Pa /dev .
81Also, print the mode of the file in octal instead of symbolic form.
82.It Fl o
83Output file offset.
84Follow the size field with the descriptor's offset.
85Useful for checking progress as a process works through a large file.
86This information is only visible to the user or superuser.
87.It Fl p Ar pid
88Report all files open by the specified process.
89This option may be specified multiple times.
90.It Fl s
91Report per file io statistics in two additional columns
92.Sq XFERS
93and
94.Sq KBYTES .
95This information is only visible to the user or superuser.
96.It Fl u Ar user
97Report all files open by the specified user.
98This option may be specified multiple times.
99.It Fl v
100Verbose mode.
101Print error messages upon failures to locate particular
102system data structures rather than silently ignoring them.
103Most of these data structures are dynamically created or deleted and it is
104possible for them to disappear while
105.Nm
106is running.
107This is normal and unavoidable since the rest of the system is running while
108.Nm
109itself is running.
110.It Ar
111Restrict reports to the specified files.
112.El
113.Pp
114The following fields are printed:
115.Bl -tag -width MOUNT
116.It Li USER
117The username of the owner of the process (effective UID).
118.It Li CMD
119The command name of the process.
120.It Li PID
121The process ID.
122.It Li FD
123The file number in the per-process open file table or one of the following
124special names:
125.Pp
126.Bl -tag -width "text" -offset indent -compact
127.It text
128executable text inode
129.It wd
130current working directory
131.It root
132root inode
133.It tr
134kernel trace file
135.El
136.Pp
137If the file number is followed by an asterisk
138.Pq Ql * ,
139the file is not an inode, but rather a socket, or there is an error.
140In this case the remainder of the line doesn't
141correspond to the remaining headers \(em the format of the line
142is described later under
143.Sx SOCKETS .
144.It Li MOUNT
145If the
146.Fl n
147flag wasn't specified, this header is present and is the
148pathname that the file system the file resides in is mounted on.
149.It Li DEV
150If the
151.Fl n
152flag is specified, this header is present and is the
153major/minor number of the device that this file resides in.
154.It Li INUM
155The inode number of the file.
156It will be followed by an asterisk
157.Pq Ql *
158if the inode is unlinked from disk.
159.It Li MODE
160The mode of the file.
161If the
162.Fl n
163flag isn't specified, the mode is printed
164using a symbolic format (see
165.Xr strmode 3 ) ;
166otherwise, the mode is printed
167as an octal number.
168.It Li R/W
169This column describes the properties of the file descriptor:
170.Pp
171.Bl -tag -width indent -compact
172.It r
173Open for reading
174.It w
175Open for writing
176.It e
177close-on-exec flag is set
178.It p
179Opened after
180.Xr pledge 2
181.El
182.Pp
183This field is useful when trying to find the processes that are
184preventing a file system from being downgraded to read-only.
185.It Li SZ | DV
186If the file is not a character or block special file, prints the size of
187the file in bytes.
188Otherwise, if the
189.Fl n
190flag is not specified, prints
191the name of the special file as located in
192.Pa /dev .
193If that cannot be located, or the
194.Fl n
195flag is specified, prints the major/minor device
196number that the special device refers to.
197.It Li NAME
198If filename arguments are specified and the
199.Fl f
200flag is not, then
201this field is present and is the name associated with the given file.
202Normally the name cannot be determined since there is no mapping
203from an open file back to the directory entry that was used to open
204that file.
205Also, since different directory entries may reference
206the same file (via
207.Xr ln 1 ) ,
208the name printed may not be the actual
209name that the process originally used to open that file.
210.It Li XFERS
211Displays number of total data transfers performed on the file.
212.It Li KBYTES
213Displays total number of Kbytes written and read to the file.
214.El
215.Sh SOCKETS
216The formatting of open sockets depends on the protocol domain.
217In all cases the first field is the domain name
218and the second field is the socket type (stream, dgram, etc).
219The remaining fields are protocol dependent.
220For TCP, it is the address of the tcpcb, and for UDP, the inpcb (socket pcb).
221For
222.Ux Ns -domain
223sockets, it's the address of the socket pcb and the address
224of the connected pcb (if connected).
225Otherwise the protocol number and address of the socket itself are printed.
226The attempt is to make enough information available to
227permit further analysis without duplicating
228.Xr netstat 1 .
229.Pp
230For example, the addresses mentioned above are the addresses which the
231.Ic netstat -A
232command would print for TCP, UDP, and
233.Ux Ns -domain.
234These addresses are only visible to the superuser, otherwise 0x0 is printed.
235Sockets that have been disassociated from a protocol control block
236will always print 0x0.
237A unidirectional
238.Ux Ns -domain
239socket indicates the direction of flow with
240an arrow
241.Pf ( Dq <-
242or
243.Dq -> ) ,
244and a full duplex socket shows a double arrow
245.Pq Dq <-> .
246.Pp
247For
248.Dv AF_INET
249and
250.Dv AF_INET6
251sockets,
252.Nm
253also attempts to print the internet address and port for the
254local end of a connection.
255If the socket is connected, it also prints the remote internet address
256and port.
257A
258.Ql *
259is used to indicate an
260.Dv INADDR_ANY
261binding.
262In this case, the
263use of the arrow
264.Pf ( Dq <--
265or
266.Dq --> )
267indicates the direction the socket connection was created.
268.Pp
269If the socket has been spliced to or from another socket (see
270.Xr setsockopt 2
271and
272.Dv SO_SPLICE )
273then
274.Nm
275prints a thick arrow
276.Pf ( Dq <==> ,
277.Dq <== ,
278or
279.Dq ==> ) ,
280followed by the address and endpoint information of the other socket
281in the splice,
282if available.
283.Sh PIPES
284Every pipe is printed as an address which is the same for both sides of
285the pipe and a state that is built of the letters
286.Dq RWE .
287W \- The pipe blocks waiting for the reader to read data.
288R \- The pipe blocks waiting for the writer to write data.
289E \- The pipe is in EOF state.
290.Sh KQUEUE
291Each
292.Xr kqueue 2
293is printed with some information as to queue length.
294Since these things are normally serviced quickly, it is likely that
295nothing of real importance can be discerned.
296.Sh SEE ALSO
297.Xr netstat 1 ,
298.Xr nfsstat 1 ,
299.Xr ps 1 ,
300.Xr systat 1 ,
301.Xr top 1 ,
302.Xr iostat 8 ,
303.Xr pstat 8 ,
304.Xr tcpdrop 8 ,
305.Xr vmstat 8
306.Sh HISTORY
307The
308.Nm
309command appeared in
310.Bx 4.3 tahoe .
311.Sh CAVEATS
312Sockets in use by the kernel, such as those opened by
313.Xr nfsd 8 ,
314will not be seen by
315.Nm ,
316even though they appear in
317.Xr netstat 1 .
318.Sh BUGS
319Since
320.Nm
321takes a snapshot of the system, it is only correct for a very short period
322of time.
323.Pp
324Moreover, because DNS resolution and YP lookups cause many file
325descriptor changes,
326.Nm
327does not attempt to translate the internet address and port numbers into
328symbolic names.
329