NAME
df - report filesystem disk space usage
SYNOPSIS
df [OPTION]... [FILE]...
DESCRIPTION
This manual page documents the GNU version of df. df displays the amount of disk space available on the filesystem containing each file name argument. If no file name is given, the space available on all currently mounted filesystems is shown. Disk space is shown in 1K blocks by default, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used.
If an argument is the absolute file name of a disk device node containing a mounted filesystem, df shows the space available on that filesystem rather than on the filesystem containing the device node (which is always the root filesystem). This version of df cannot show the space available on unmounted filesystems, because on most kinds of systems doing so requires very nonportable intimate knowledge of filesystem structures.

OPTIONS
Show information about the filesystem on which each FILE resides, or all filesystems by default.

Mandatory arguments to long options are mandatory for short options too.

-a, --all
include filesystems having 0 blocks
-B, --block-size=SIZE use SIZE-byte blocks
-h, --human-readable
print sizes in human readable format (e.g., 1K 234M 2G)
-H, --si
likewise, but use powers of 1000 not 1024
-i, --inodes
list inode information instead of block usage
-k
like --block-size=1K
-l, --local
limit listing to local filesystems
--no-sync
do not invoke sync before getting usage info (default)
-P, --portability
use the POSIX output format
--sync
invoke sync before getting usage info
-t, --type=TYPE
limit listing to filesystems of type TYPE
-T, --print-type
print filesystem type
-x, --exclude-type=TYPE
limit listing to filesystems not of type TYPE
-v
(ignored)
--help
display this help and exit
--version
output version information and exit
SIZE may be (or may be an integer optionally followed by) one of following: kB 1000, K 1024, MB 1000*1000, M 1024*1024, and so on for G, T, P, E, Z, Y.