Disk Free – display free disk space.
With no arguments, &qt;df&qt;&qt; reports the space used and available on all currently mounted filesystems (of all types). Otherwise, &qt;df&qt;&qt; reports on the filesystem containing each argument file.
SYNTAX
df [option]… [file]…
Normally the disk space is printed in units of 1024 bytes, but this
can be overridden.
OPTIONS
&qt;-a&qt;&qt;
&qt;–all&qt;&qt;
Include in the listing filesystems that have a size of 0 blocks,
which are omitted by default. Such filesystems are typically
special-purpose pseudo-filesystems, such as automounter entries.
Also, filesystems of type "ignore" or "auto", supported by some
operating systems, are only included if this option is specified.
&qt;-h&qt;&qt;
&qt;–human-readable&qt;&qt;
Append a size letter such as &qt;M&qt;&qt; for megabytes to each size.
Powers of 1024 are used, not 1000; &qt;M&qt;&qt; stands for 1,048,576 bytes.
Use the &qt;-H&qt;&qt; or &qt;–si&qt;&qt; option if you prefer powers of 1000.
&qt;-H&qt;&qt;
&qt;–si&qt;&qt;
Append a size letter such as &qt;M&qt;&qt; for megabytes to each size. (SI
is the International System of Units, which defines these letters
as prefixes.) Powers of 1000 are used, not 1024; &qt;M&qt;&qt; stands for
1,000,000 bytes. Use the &qt;-h&qt;&qt; or &qt;–human-readable&qt;&qt; option if you
prefer powers of 1024.
&qt;-i&qt;&qt;
&qt;–inodes&qt;&qt;
List inode usage information instead of block usage. An inode
(short for index node) is contains information about a file such
as its owner, permissions, timestamps, and location on the disk.
&qt;-k&qt;&qt;
&qt;–kilobytes&qt;&qt;
Print sizes in 1024-byte blocks, overriding the default block size.
&qt;-l&qt;&qt;
&qt;–local&qt;&qt;
Limit the listing to local filesystems. By default, remote
filesystems are also listed.
&qt;-m&qt;&qt;
&qt;–megabytes&qt;&qt;
Print sizes in megabyte (that is, 1,048,576-byte) blocks.
&qt;–no-sync&qt;&qt;
Do not invoke the &qt;sync&qt;&qt; system call before getting any usage data.
This may make &qt;df&qt;&qt; run significantly faster on systems with many
disks, but on some systems (notably SunOS) the results may be
slightly out of date. This is the default.
&qt;-P&qt;&qt;
&qt;–portability&qt;&qt;
Use the POSIX output format. This is like the default format
except that the information about each filesystem is always
printed on exactly one line; a mount device is never put on a line
by itself. This means that if the mount device name is more than
20 characters long (e.g., for some network mounts), the columns
are misaligned.
&qt;–sync&qt;&qt;
Invoke the &qt;sync&qt;&qt; system call before getting any usage data. On
some systems (notably SunOS), doing this yields more up to date
results, but in general this option makes &qt;df&qt;&qt; much slower,
especially when there are many or very busy filesystems.
&qt;-t FSTYPE&qt;&qt;
&qt;–type=FSTYPE&qt;&qt;
Limit the listing to filesystems of type FSTYPE. Multiple
filesystem types can be specified by giving multiple &qt;-t&qt;&qt; options.
By default, nothing is omitted.
&qt;-T&qt;&qt;
&qt;–print-type&qt;&qt;
Print each filesystem&qt;&qt;s type. The types printed here are the same
ones you can include or exclude with &qt;-t&qt;&qt; and &qt;-x&qt;&qt;. The particular
types printed are whatever is supported by the system. Here are
some of the common names (this list is certainly not exhaustive):
&qt;nfs&qt;&qt;
An NFS filesystem, i.e., one mounted over a network from
another machine. This is the one type name which seems to be
used uniformly by all systems.
&qt;4.2, ufs, efs…&qt;&qt;
A filesystem on a locally-mounted hard disk. (The system
might even support more than one type here; Linux does.)
&qt;hsfs, cdfs&qt;&qt;
A filesystem on a CD-ROM drive. HP-UX uses &qt;cdfs&qt;&qt;, most other
systems use &qt;hsfs&qt;&qt; (&qt;hs&qt;&qt; for &qt;High Sierra&qt;&qt;).
&qt;pcfs&qt;&qt;
An MS-DOS filesystem, usually on a diskette.
&qt;-x FSTYPE&qt;&qt;
&qt;–exclude-type=FSTYPE&qt;&qt;
Limit the listing to filesystems not of type FSTYPE. Multiple
filesystem types can be eliminated by giving multiple &qt;-x&qt;&qt;
options. By default, no filesystem types are omitted.
&qt;-v&qt;&qt;
Ignored; for compatibility with System V versions of &qt;df&qt;&qt;.If an argument FILE is a disk device file containing a mounted filesystem, &qt;df&qt;&qt; shows the space available on that filesystem rather than on the filesystem containing the device node (i.e., the root filesystem). GNU &qt;df&qt;&qt; does not attempt to determine the disk usage on unmounted filesystems, because on most kinds of systems doing so requires extremely nonportable intimate knowledge of filesystem structures.