Linux and Unix df command
df displays the amount of disk space available on the file system containing each file name argument. If no file name is given, the space available on all currently mounted file systems 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 file system, df shows the space available on that file system rather than on the file system containing the device node (which is always the root file system). df cannot show the space available on unmounted file systems, because on most kinds of systems doing so requires very system-specific knowledge of file system structures.
df [OPTION]... [FILE]...
|-a, --all||include dummy file systems.|
|-B, --block-size=SIZE||scale sizes by SIZE before printing them. E.g., '-BM' prints sizes in units of 1,048,576 bytes. See "SIZE Format" below for more information.|
|--total||display a grand total.|
|-h, --human-readable||print sizes in human readable format (e.g., 1K 234M 2G)|
|-H, --si||same as -h, but use powers of 1000 instead of 1024.|
|-i, --inodes||list inode information instead of block usage.|
|-l, --local||limit listing to local file systems|
|--no-sync||do not invoke a sync before getting usage info (This is the default).|
|-P, --portability||use the POSIX output format.|
|--sync||invoke a sync before getting usage info.|
|-t, --type=TYPE||limit listing to file systems of type TYPE.|
|-T, --print-type||print file system type.|
|-x, --exclude-type=TYPE||limit listing to file systems not of type TYPE.|
|-v||(ignored; included for compatibility reasons.)|
|--help||display a help message and exit.|
|--version||output version information and exit.|
Display values are in units of the first available SIZE from --block-size, and the DF_BLOCK_SIZE, BLOCK_SIZE and BLOCKSIZE environment variables. Otherwise, units default to 1024 bytes (or 512 if POSIXLY_CORRECT is set).
Display all file systems and their disk usage, as in the following output:
Filesystem 1K-blocks Used Available Use% Mounted on /dev/loop0 18761008 15246876 2554440 86% / none 4 0 4 0% /sys/fs/cgroup udev 493812 4 493808 1% /dev tmpfs 100672 1364 99308 2% /run none 5120 0 5120 0% /run/lock none 503352 1764 501588 1% /run/shm none 102400 20 102380 1% /run/user /dev/sda3 174766076 164417964 10348112 95% /host
Same as above, but use "human readable" formatting, as in the following example:
Filesystem Size Used Avail Use% Mounted on /dev/loop0 18G 15G 2.5G 86% / none 4.0K 0 4.0K 0% /sys/fs/cgroup udev 483M 4.0K 483M 1% /dev tmpfs 99M 1.4M 97M 2% /run none 5.0M 0 5.0M 0% /run/lock none 492M 1.8M 490M 1% /run/shm none 100M 20K 100M 1% /run/user /dev/sda3 167G 157G 9.9G 95% /host
Display the amount of free space in the public_html directory, as in the following output:
Filesystem 1K-blocks Used Available Use% Mounted on /dev/loop0 18761008 15246924 2554392 86% /