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third_party/cpp/googleapis/README.md

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+# Google Cloud Platform C++ Proto Libraries
+
+Compile the protocol buffer definitions into C++ libraries.
+
+## Requirements
+
+#### Compiler
+
+The Google Cloud C++ libraries are tested with the following compilers:
+
+| Compiler    | Minimum Version |
+| ----------- | --------------- |
+| GCC         | 4.8 |
+| Clang       | 3.8 |
+| MSVC++      | 14.1 |
+| Apple Clang | 8.1 |
+
+#### Build Tools
+
+The Google Cloud C++ Client Libraries can be built with
+[CMake](https://cmake.org) or [Bazel](https://bazel.io).  The minimal versions
+of these tools we test with are:
+
+| Tool       | Minimum Version |
+| ---------- | --------------- |
+| CMake      | 3.5 |
+| Bazel      | 0.24.0 |
+
+#### Libraries
+
+The libraries also depend on gRPC, libcurl, and the dependencies of those
+libraries. The Google Cloud C++ Client libraries are tested with the following
+versions of these dependencies:
+
+| Library | Minimum version |
+| ------- | --------------- |
+| gRPC    | v1.16.x |
+| libcurl | 7.47.0  |
+
+
+## Versioning
+
+Please note that the Google Cloud C++ client libraries do **not** follow
+[Semantic Versioning](http://semver.org/).
+
+**GA**: Libraries defined at a GA quality level are expected to be stable and
+any backwards-incompatible changes will be noted in the documentation. Major
+changes to the API will signaled by changing major version number
+(e.g. 1.x.y -> 2.0.0).
+
+**Beta**: Libraries defined at a Beta quality level are expected to be mostly
+stable and we're working towards their release candidate. We will address issues
+and requests with a higher priority.
+
+**Alpha**: Libraries defined at an Alpha quality level are still a
+work-in-progress and are more likely to get backwards-incompatible updates.
+Additionally, it's possible for Alpha libraries to get deprecated and deleted
+before ever being promoted to Beta or GA.
+
+## Contributing changes
+
+See [`CONTRIBUTING.md`](CONTRIBUTING.md) for details on how to contribute to
+this project, including how to build and test your changes as well as how to
+properly format your code.
+
+## Licensing
+
+Apache 2.0; see [`LICENSE`](LICENSE) for details.