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        This module depends on `lib/common` and `lib/decompress`.
        To enable this feature, define `ZSTD_LEGACY_SUPPORT` during compilation.
        Specifying a number limits versions supported to that version onward.
        For example, `ZSTD_LEGACY_SUPPORT=2` means : "support legacy formats >= v0.2.0".
        Conversely, `ZSTD_LEGACY_SUPPORT=0` means "do __not__ support legacy formats".
        By default, this build macro is set as `ZSTD_LEGACY_SUPPORT=5`.
        Decoding supported legacy format is a transparent capability triggered within decompression functions.
        It's also allowed to invoke legacy API directly, exposed in `lib/legacy/zstd_legacy.h`.
        Each version does also provide its own set of advanced API.
        For example, advanced API for version `v0.4` is exposed in `lib/legacy/zstd_v04.h` .

- While invoking `make libzstd`, it's possible to define build macros
        `ZSTD_LIB_COMPRESSION, ZSTD_LIB_DECOMPRESSION`, `ZSTD_LIB_DICTBUILDER`,
        and `ZSTD_LIB_DEPRECATED` as `0` to forgo compilation of the corresponding features.
        This will also disable compilation of all dependencies
        (eg. `ZSTD_LIB_COMPRESSION=0` will also disable dictBuilder).

- There are some additional build macros that can be used to minify the decoder.

  Zstandard often has more than one implementation of a piece of functionality,
  where each implementation optimizes for different scenarios. For example, the
  Huffman decoder has complementary implementations that decode the stream one
  symbol at a time or two symbols at a time. Zstd normally includes both (and
  dispatches between them at runtime), but by defining `HUF_FORCE_DECOMPRESS_X1`
  or `HUF_FORCE_DECOMPRESS_X2`, you can force the use of one or the other, avoiding
  compilation of the other. Similarly, `ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT`
  and `ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG` force the compilation and use of
  only one or the other of two decompression implementations. The smallest
  binary is achieved by using `HUF_FORCE_DECOMPRESS_X1` and
  `ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT`.

  For squeezing the last ounce of size out, you can also define
  `ZSTD_NO_INLINE`, which disables inlining, and `ZSTD_STRIP_ERROR_STRINGS`,
  which removes the error messages that are otherwise returned by
  `ZSTD_getErrorName`.

- While invoking `make libzstd`, the build macro `ZSTD_LEGACY_MULTITHREADED_API=1`
  will expose the deprecated `ZSTDMT` API exposed by `zstdmt_compress.h` in
  the shared library, which is now hidden by default.


#### Windows : using MinGW+MSYS to create DLL

DLL can be created using MinGW+MSYS with the `make libzstd` command.
This command creates `dll\libzstd.dll` and the import library `dll\libzstd.lib`.
The import library is only required with Visual C++.
The header file `zstd.h` and the dynamic library `dll\libzstd.dll` are required to
compile a project using gcc/MinGW.
The dynamic library has to be added to linking options.
It means that if a project that uses ZSTD consists of a single `test-dll.c`
file it should be linked with `dll\libzstd.dll`. For example:
```
    gcc $(CFLAGS) -Iinclude/ test-dll.c -o test-dll dll\libzstd.dll
```
The compiled executable will require ZSTD DLL which is available at `dll\libzstd.dll`.


#### Deprecated API

Obsolete API on their way out are stored in directory `lib/deprecated`.
At this stage, it contains older streaming prototypes, in `lib/deprecated/zbuff.h`.
These prototypes will be removed in some future version.
Consider migrating code towards supported streaming API exposed in `zstd.h`.


#### Miscellaneous

The other files are not source code. There are :

 - `BUCK` : support for `buck` build system (https://buckbuild.com/)
 - `Makefile` : `make` script to build and install zstd library (static and dynamic)
 - `README.md` : this file
 - `dll/` : resources directory for Windows compilation
 - `libzstd.pc.in` : script for `pkg-config` (used in `make install`)