These docs are under active development and cover the v0.20 Kobicha security model.
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df

df — "disk free" — reports, for each file system, how much space it has and how much is still available.

df [options] [file...]

With no arguments, df reports on every mounted file system. Given a file, it reports on the one file system that file lives on.

$ df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda2       456G  198G  235G  46% /
/dev/sda1       511M   12M  499M   3% /boot

The default columns

Each line is one file system:

  • Filesystem — the device or source backing it.
  • Size — its total capacity.
  • Used — space in use.
  • Avail — space still available.
  • Use% — used space as a percentage.
  • Mounted on — where it is attached in the directory tree.

Choosing the units

By default sizes are shown in blocks. These options change that.

Option Effect
-h, --human-readable Show sizes with unit suffixes — 456G, 12M — using powers of 1024.
-H, --si Likewise, but using powers of 1000.
-B, --block-size=SIZE Show sizes scaled to SIZE — -BM reports in megabytes.
-k Use 1024-byte blocks.

Choosing what to report

Option Effect
-a, --all Include dummy and otherwise-hidden file systems that df would normally skip.
-l, --local Report only local file systems, skipping network-mounted ones.
-t, --type=TYPE Report only file systems of type TYPE.
-x, --exclude-type=TYPE Report everything except file systems of type TYPE.
--total Add a final line giving the grand total across everything reported.

Changing the output

Option Effect
-i, --inodes Report inode counts — total, used, and free — instead of block space. A file system can run out of inodes while it still has space.
-T, --print-type Add a column showing each file system's type.
--output[=LIST] Replace the default columns with exactly the fields named in LIST. With no list, print every available field.
-P, --portability Use a fixed, simple column layout that does not wrap a long device name onto its own line.

Sync behaviour

Option Effect
--sync Flush pending writes before reading the usage figures, for the most up-to-date numbers.
--no-sync Do not flush first. This is the default and is faster.

Exit status

Code Meaning
0 The report was produced.
1 A failure — for example, a named file does not exist, or the table of file systems could not be read.

See also