df adalah command yang berarti “disk filesystem

Usage: df [OPTION]… [FILE]…
 Show information about the file system on which each FILE resides,
 or all file systems by default.
 Mandatory arguments to long options are mandatory for short options too.
   -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.
   -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 file systems
       --no-sync         do not invoke sync before getting usage info (default)
       --output[=FIELD_LIST]  use the output format defined by FIELD_LIST,
                                or print all fields if FIELD_LIST is omitted.
   -P, --portability     use the POSIX output format
       --sync            invoke sync before getting usage info
       --total           elide all entries insignificant to available space,
                           and produce a grand total
   -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)
       --help     display this help 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).
 SIZE is an integer and optional unit (example: 10M is 1010241024).  Units
 are K, M, G, T, P, E, Z, Y (powers of 1024) or KB, MB, … (powers of 1000).
 FIELD_LIST is a comma-separated list of columns to be included.  Valid
 field names are: 'source', 'fstype', 'itotal', 'iused', 'iavail', 'ipcent',
 'size', 'used', 'avail', 'pcent' and 'target' (see info page).
 Report df bugs to bug-coreutils@gnu.org
 GNU coreutils home page: http://www.gnu.org/software/coreutils/
 General help using GNU software: http://www.gnu.org/gethelp/
 For complete documentation, run: info coreutils 'df invocation'