# du

_Peios / Using Peios / Peiosutils / Files and directories_

> Report how much disk space files and directories use.

`du` — "disk usage" — reports how much space files and directories occupy. Where [`df`](/peios/using-peios/peiosutils/files-and-directories/df.md) tells you about a whole file system, `du` tells you where the space has actually gone.

```
du [options] [file...]
```

```
$ du -sh /home/jack/projects
4.2G    /home/jack/projects
```

With no arguments, `du` works on the current directory. By default it walks the directory tree, prints the cumulative size of **each directory** (a directory's size includes everything under it), and ends with the total for the argument itself. Individual files are not listed unless you ask for them.

## What to count and how deep

| Option | Effect |
|---|---|
| `-a`, `--all` | List every file, not only directories. |
| `-s`, `--summarize` | Print only a single total for each argument — no per-subdirectory breakdown. |
| `-d`, `--max-depth=N` | Show totals only down to `N` levels below each argument. `-d 0` is the same as `-s`. |
| `-S`, `--separate-dirs` | Give each directory's *own* size, excluding its subdirectories. |
| `-c`, `--total` | Add a final grand-total line. |
| `--inodes` | Count inodes used rather than space used. |

## What "size" means

| Option | Effect |
|---|---|
| `-h`, `--human-readable` | Sizes with unit suffixes — `4.2G` — using powers of 1024. |
| `--si` | Likewise, using powers of 1000. |
| `-B`, `--block-size=SIZE` | Scale sizes to `SIZE`. |
| `-k` / `-m` | Use 1024-byte / 1024×1024-byte units. |
| `--apparent-size` | Report the apparent size of files — how much data they contain — rather than the disk space they occupy. The two differ for sparse files and because of block rounding. |
| `-b`, `--bytes` | Report plain byte counts. Equivalent to `--apparent-size --block-size=1`. |

## Following symbolic links

By default `du` does not follow symbolic links.

| Option | Effect |
|---|---|
| `-L`, `--dereference` | Follow all symbolic links and count what they point to. |
| `-D`, `-H`, `--dereference-args` | Follow only the symbolic links named directly on the command line. |
| `-P`, `--no-dereference` | Follow no symbolic links. This is the default. |
| `-x`, `--one-file-system` | Do not cross into a different file system while walking. |
| `-l`, `--count-links` | Count a hard-linked file every time it is encountered, instead of once. |

## Limiting the output

| Option | Effect |
|---|---|
| `--exclude=PATTERN` | Skip files and directories whose name matches `PATTERN`. |
| `--exclude-from=FILE` | Skip everything matching any pattern listed in `FILE`. |
| `-t`, `--threshold=SIZE` | Show only entries at least `SIZE` (or, with a negative `SIZE`, at most that big). |
| `--files0-from=F` | Take the list of files to measure from `F`, NUL-separated. `-` means standard input. |
| `--time[=WORD]` | Also show a timestamp — by default the latest modification time anywhere in the directory. |
| `-0`, `--null` | End each output line with a NUL character instead of a newline. |
| `-v`, `--verbose` | Report extra detail about what is being processed. |

## Exit status

| Code | Meaning |
|---|---|
| `0` | The report was produced. |
| `1` | A file or directory could not be accessed. |

Related content:

- [df](/peios/using-peios/peiosutils/files-and-directories/df.md)
- [Files and directories](/peios/using-peios/peiosutils/files-and-directories/overview.md)