Cameron Katri's Manual Page Server

Manual Page Search Parameters
DF(1) General Commands Manual DF(1)

df — display free disk space

df [-b | -h | -H | -k | -m | -g | -P] [-ailn] [-t] [-T type] [file | filesystem ...]

df [-b | -h | -H | -k | -m | -P] [-ailn] [-t type] [-T type] [file | filesystem ...]

The df utility displays statistics about the amount of free disk space on the specified filesystem or on the filesystem of which file is a part. Values are displayed in 512-byte per block counts. If neither a file or a filesystem operand is specified, statistics for all mounted filesystems are displayed (subject to the -t option below).

The following options are available:

Show all mount points, including those that were mounted with the MNT_IGNORE flag.
Use (the default) 512-byte blocks. This is only useful as a way to override an BLOCKSIZE specification from the environment.
Use 1073741824-byte (1-Gbyte) blocks rather than the default. Note that this overrides the BLOCKSIZE specification from the environment.
"Human-readable" output. Use unit suffixes: Byte, Kilobyte, Megabyte, Gigabyte, Terabyte and Petabyte in order to reduce the number of digits to three or less using base 10 for sizes.
"Human-readable" output. Use unit suffixes: Byte, Kilobyte, Megabyte, Gigabyte, Terabyte and Petabyte in order to reduce the number of digits to three or less using base 2 for sizes.
Include statistics on the number of free inodes. This option is now the default to conform to Version 3 of the Single UNIX Specification (“SUSv3”) Use -P to suppress this output.
Use 1024-byte (1-Kbyte) blocks, rather than the default. Note that this overrides the BLOCKSIZE specification from the environment.
Only display information about locally-mounted filesystems.
Use 1048576-byte (1-Mbyte) blocks rather than the default. Note that this overrides the BLOCKSIZE specification from the environment.
Print out the previously obtained statistics from the filesystems. This option should be used if it is possible that one or more filesystems are in a state such that they will not be able to provide statistics without a long delay. When this option is specified, df will not request new statistics from the filesystems, but will respond with the possibly stale statistics that were previously obtained.
Use (the default) 512-byte blocks. This is only useful as a way to override an BLOCKSIZE specification from the environment.
Only print out statistics for filesystems of the specified types. More than one type may be specified in a comma separated list. The list of filesystem types can be prefixed with “no” to specify the filesystem types for which action should be taken. For example, the df command: 
df -T nonfs,mfs

lists all filesystems except those of type NFS and MFS. The lsvfs(1) command can be used to find out the types of filesystems that are available on the system.

If used with no arguments, this option is a no-op (Mac OS X already prints the total allocated-space figures). If used with an argument, it acts like -T, but this usage is deprecated and should not be relied upon.

If the environment variable BLOCKSIZE is set, the block counts will be displayed in units of that size block.

The -n and -t flags are ignored if a file or filesystem is specified.

The "capacity" percentage is normally rounded up to the next higher integer. In legacy mode, it is rounded down to the next lower integer.

When the -P option and the -k option are used together, sizes are reported in 1024-blocks. In legacy mode, when the -P option and -k option are used together, the last option specified dictates the reported block size.

The -t option is normally a no-op (Mac OS X already prints the total allocated-space figures). In legacy mode, it is equivalent to -T.

For more information about legacy mode, see compat(5).

lsvfs(1), quota(1), fstatfs(2), getfsstat(2), statfs(2), getmntinfo(3), compat(5), fstab(5), mount(8), quot(8)

A df command appeared in Version 1 AT&T UNIX.

May 8, 1995 macOS