/nix/store/2hy5bxw7xgbgxkn0i4x6hjr8w3dbx16c-source

$ ls /nix/store/2hy5bxw7xgbgxkn0i4x6hjr8w3dbx16c-source
patchelf-0.18.0
```
::::

::::{.example #ex-fetchers-fetchzip-rar-archive}
# Using `fetchzip` to decompress a `.rar` file

The `unrar` package provides a [setup hook](#ssec-setup-hooks) to decompress `.rar` archives during the [unpack phase](#ssec-unpack-phase), which can be used with `fetchzip` to decompress those archives:

```nix
{ fetchzip, unrar }:
fetchzip {
  url = "https://archive.org/download/SpaceCadet_Plus95/Space_Cadet.rar";
  hash = "sha256-fC+zsR8BY6vXpUkVd6i1jF0IZZxVKVvNi6VWCKT+pA4=";
  stripRoot = false;
  nativeBuildInputs = [ unrar ];
}
```

Since this particular `.rar` file doesn't put its contents in a directory inside the archive, `stripRoot` must be set to `false`.

After building the recipe, the derivation output will show the decompressed files:

```shell
$ nix-build
(output removed for clarity)
/nix/store/zpn7knxfva6rfjja2gbb4p3l9w1f0d36-source

$ ls /nix/store/zpn7knxfva6rfjja2gbb4p3l9w1f0d36-source
FONT.DAT      PINBALL.DAT  PINBALL.EXE	PINBALL2.MID  TABLE.BMP    WMCONFIG.EXE
MSCREATE.DIR  PINBALL.DOC  PINBALL.MID	Sounds	     WAVEMIX.INF
```
::::

## `fetchpatch` {#fetchpatch}

`fetchpatch` works very similarly to `fetchurl` with the same arguments expected. It expects patch files as a source and performs normalization on them before computing the checksum. For example, it will remove comments or other unstable parts that are sometimes added by version control systems and can change over time.

- `relative`: Similar to using `git-diff`'s `--relative` flag, only keep changes inside the specified directory, making paths relative to it.
- `stripLen`: Remove the first `stripLen` components of pathnames in the patch.
- `decode`: Pipe the downloaded data through this command before processing it as a patch.
- `extraPrefix`: Prefix pathnames by this string.
- `excludes`: Exclude files matching these patterns (applies after the above arguments).
- `includes`: Include only files matching these patterns (applies after the above arguments).
- `revert`: Revert the patch.

Note that because the checksum is computed after applying these effects, using or modifying these arguments will have no effect unless the `hash` argument is changed as well.


Most other fetchers return a directory rather than a single file.


## `fetchDebianPatch` {#fetchdebianpatch}

A wrapper around `fetchpatch`, which takes:
- `patch` and `hash`: the patch's filename,
  and its hash after normalization by `fetchpatch` ;
- `pname`: the Debian source package's name ;
- `version`: the upstream version number ;
- `debianRevision`: the [Debian revision number] if applicable ;
- the `area` of the Debian archive: `main` (default), `contrib`, or `non-free`.

Here is an example of `fetchDebianPatch` in action:

```nix
{
  lib,
  fetchDebianPatch,
  buildPythonPackage,
}:

buildPythonPackage rec {
  pname = "pysimplesoap";
  version = "1.16.2";
  src = <...>;

  patches = [
    (fetchDebianPatch {
      inherit pname version;
      debianRevision = "5";
      patch = "Add-quotes-to-SOAPAction-header-in-SoapClient.patch";
      hash = "sha256-xA8Wnrpr31H8wy3zHSNfezFNjUJt1HbSXn3qUMzeKc0=";
    })
  ];

  # ...
}
```

Patches are fetched from `sources.debian.org`, and so must come from a
package version that was uploaded to the Debian archive.  Packages may
be removed from there once that specific version isn't in any suite
anymore (stable, testing, unstable, etc.), so maintainers should use
`copy-tarballs.pl` to archive the patch if it needs to be available
longer-term.



## `fetchsvn` {#fetchsvn}

Used with Subversion. Expects `url` to a Subversion directory, `rev`, and `hash`.

## `fetchgit` {#fetchgit}

Used with Git. Expects `url` to a Git repo, `rev`, and `hash`. `rev` in this case can be full the git commit id (SHA1 hash) or a tag name like `refs/tags/v1.0`.

If you want to fetch a tag you should pass the `tag` parameter instead of `rev` which has the same effect as setting `rev = "refs/tags"/${version}"`.