xref: /freebsd/bin/df/df.1 (revision 304f52ad1ba5a9783b2eb547fed33c541e1af901)

.\"-
.\" Copyright (c) 1989, 1990, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd March 29, 2023
.Dt DF 1
.Os
.Sh NAME
.Nm df
.Nd display free disk space
.Sh SYNOPSIS
.Nm
.Op Fl -libxo
.Op Fl b | g | H | h | k | m | P
.Op Fl acilnT
.Op Fl \&,
.Op Fl t Ar type
.Op Ar file | filesystem ...
.Sh DESCRIPTION
The
.Nm
utility
displays statistics about the amount of free disk space on the specified
mounted
.Ar file system
or on the file system of which
.Ar file
is a part.
By default block counts are displayed with an assumed block size of
512 bytes.
If neither a file or a file system operand is specified,
statistics for all mounted file systems are displayed
(subject to the
.Fl t
option below).
.Pp
The following options are available:
.Bl -tag -width indent
.It Fl -libxo
Generate output via
.Xr libxo 3
in a selection of different human and machine readable formats.
See
.Xr xo_parse_args 3
for details on command line arguments.
.It Fl a
Show all mount points, including those that were mounted with the
.Dv MNT_IGNORE
flag.
This is implied for file systems specified on the command line.
.It Fl b
Explicitly use 512 byte blocks, overriding any
.Ev BLOCKSIZE
specification from the environment.
This is the same as the
.Fl P
option.
The
.Fl k
option overrides this option.
.It Fl c
Display a grand total.
.It Fl g
Use 1073741824 byte (1 Gibibyte) blocks rather than the default.
This overrides any
.Ev BLOCKSIZE
specification from the environment.
.It Fl h
.Dq Human-readable
output.
Use unit suffixes: Byte, Kibibyte, Mebibyte, Gibibyte, Tebibyte and
Pebibyte (based on powers of 1024) in order to reduce the number of
digits to four or fewer.
.It Fl H , Fl Fl si
Same as
.Fl h
but based on powers of 1000.
.It Fl i
Include statistics on the number of free and used inodes.
In conjunction with the
.Fl h
or
.Fl H
options, the number of inodes is scaled by powers of 1000.
In case the filesystem has no inodes then
.Sq -
is displayed instead of the usage percentage.
.It Fl k
Use 1024 byte (1 Kibibyte) blocks rather than the default.
This overrides the
.Fl P
option and any
.Ev BLOCKSIZE
specification from the environment.
.It Fl l
Select a locally-mounted file system for display.
If used in combination with the
.Fl t Ar type
option, file system types will be added or excluded according to the
parameters of that option.
.It Fl m
Use 1048576 byte (1 Mebibyte) blocks rather than the default.
This overrides any
.Ev BLOCKSIZE
specification from the environment.
.It Fl n
Print out the previously obtained statistics from the file systems.
This option should be used if it is possible that one or more
file systems are in a state such that they will not be able to provide
statistics without a long delay.
When this option is specified,
.Nm
will not request new statistics from the file systems, but will respond
with the possibly stale statistics that were previously obtained.
.It Fl P
Explicitly use 512 byte blocks, overriding any
.Ev BLOCKSIZE
specification from the environment.
This is the same as the
.Fl b
option.
The
.Fl k
option overrides this option.
.It Fl t Ar type
Select file systems to display.
More than one type may be specified in a comma separated list.
The list of file system types can be prefixed with
.Dq no
to specify the file system types for which action should
.Em not
be taken.
If used in combination with the
.Fl l
option, the parameters of this option will modify the list of
locally-mounted file systems selected by the
.Fl l
option.
For example, the
.Nm
command:
.Bd -literal -offset indent
df -t nonfs,nullfs
.Ed
.Pp
lists all file systems except those of type NFS and NULLFS.
The
.Xr lsvfs 1
command can be used to find out the types of file systems
that are available on the system.
.It Fl T
Include file system type.
.It Fl ,
(Comma) Print sizes grouped and separated by thousands using the
non-monetary separator returned by
.Xr localeconv 3 ,
typically a comma or period.
If no locale is set, or the locale does not have a non-monetary separator, this
option has no effect.
.El
.Sh ENVIRONMENT
.Bl -tag -width BLOCKSIZE
.It Ev BLOCKSIZE
Specifies the units in which to report block counts.
This uses
.Xr getbsize 3 ,
which allows units of bytes or numbers scaled with the letters
.Em k
(for multiples of 1024 bytes),
.Em m
(for multiples of 1048576 bytes) or
.Em g
(for gibibytes).
The allowed range is 512 bytes to 1 GB.
If the value is outside, it will be set to the appropriate limit.
.El
.Sh EXAMPLES
Show human readable free disk space for all mount points including file system
type:
.Bd -literal -offset indent
$ df -ahT
Filesystem   Type        Size    Used   Avail Capacity  Mounted on
/dev/ada1p2  ufs         213G    152G     44G    78%    /
devfs        devfs       1.0K    1.0K      0B   100%    /dev
/dev/ada0p1  ufs         1.8T    168G    1.5T    10%    /data
linsysfs     linsysfs    4.0K    4.0K      0B   100%    /compat/linux/sys
/dev/da0     msdosfs     7.6G    424M    7.2G     5%    /mnt/usb
.Ed
.Pp
Show previously collected data including inode statistics except for devfs or
linsysfs file systems.
Note that the
.Dq no
prefix affects all the file systems in the list and the
.Fl t
option can be specified only once:
.Bd -literal -offset indent
$ df -i -n -t nodevfs,linsysfs
Filesystem   1K-blocks      Used      Avail Capacity iused     ifree %iused
Mounted on
/dev/ada1p2  223235736 159618992   45757888    78% 1657590  27234568    6%   /
/dev/ada0p1 1892163184 176319420 1564470712    10% 1319710 243300576    1%
/data
/dev/da0       7989888    433664    7556224     5%       0         0  100%
/mnt/usb
.Ed
.Pp
Show human readable information for the file system containing the file
.Pa /etc/rc.conf :
.Bd -literal -offset indent
$ df -h /etc/rc.conf
Filesystem     Size    Used   Avail Capacity  Mounted on
/dev/ada1p2    213G    152G     44G    78%    /
.Ed
.Pp
Same as above but specifying some file system:
.Bd -literal -offset indent
$ df -h /dev/ada1p2
Filesystem     Size    Used   Avail Capacity  Mounted on
/dev/ada1p2    213G    152G     44G    78%    /
.Ed
.Sh NOTES
For non-Unix file systems, the reported values of used and free inodes
may have a different meaning than that of used and available files and
directories.
An example is msdosfs, which in the case of FAT12 or FAT16 file systems
reports the number of available and free root directory entries instead
of inodes
.Po
where 1 to 21 such directory entries are required to store
each file or directory name or disk label
.Pc .
.Sh SEE ALSO
.Xr lsvfs 1 ,
.Xr quota 1 ,
.Xr fstatfs 2 ,
.Xr getfsstat 2 ,
.Xr statfs 2 ,
.Xr getbsize 3 ,
.Xr getmntinfo 3 ,
.Xr libxo 3 ,
.Xr localeconv 3 ,
.Xr xo_parse_args 3 ,
.Xr fstab 5 ,
.Xr mount 8 ,
.Xr pstat 8 ,
.Xr quot 8 ,
.Xr swapinfo 8
.Sh STANDARDS
With the exception of most options,
the
.Nm
utility conforms to
.St -p1003.1-2004 ,
which defines only the
.Fl k , P
and
.Fl t
options.
.Sh HISTORY
A
.Nm
command appeared in
.At v1 .
.Sh BUGS
The
.Fl n
flag is ignored if a file or file system is specified.
Also, if a mount
point is not accessible by the user, it is possible that the file system
information could be stale.
.Pp
The
.Fl b
and
.Fl P
options are identical.
The former comes from the BSD tradition, and the latter is required
for
.St -p1003.1-2004
conformity.