freebsd-dev/bin/df/df.1

.\"-
.\" 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.
.\" 4. 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.
.\"
.\"     @(#)df.1	8.3 (Berkeley) 5/8/95
.\" $FreeBSD$
.\"
.Dd December 1, 2015
.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
.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
.Dq Human-readable
output.
Use unit suffixes: Byte, Kilobyte, Megabyte,
Gigabyte, Terabyte and Petabyte (based on powers of 1000) in order to
reduce the number of
digits to four or fewer.
.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.
.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
Only display information about locally-mounted file systems.
.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
Only print out statistics for file systems of the specified types.
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.
For example, the
.Nm
command:
.Bd -literal -offset indent
df -t nonfs,nullfs
.Ed
.Pp
lists all file systems except those of type
.Tn NFS
and
.Tn 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 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.