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README.md

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+#vcpkg-action
+
+`vcpkg-action` is a simple action to build and cache vcpkg packages. It currently only supports Windows. `vcpkg` is cloned in the `${{ github.workspace }}\vcpkg` directory, and the build products are located in `${{ github.workspace }}\vcpkg\installed\<triplet>`. For cmake, use the option:
+
+```
+ -DCMAKE_TOOLCHAIN_FILE=${{ github.workspace }}/vcpkg/scripts/buildsystems/vcpkg.cmake
+        -DVCPKG_TARGET_TRIPLET=<triplet>
+```
+
+Another directory named `vcpkg_cache` is created in the workspace root. This directory is used to store the cache files, and is cached using `pat-s/always-upload-cache@v3`. The cache key is automatically generated, but can also be modified using the `cache-key` argument.
+
+Example usage:
+
+```yaml
+- name: vcpkg build
+  uses: johnwason/vcpkg-action@v1
+  with:
+    pkgs: boost-date-time boost-system
+    triplet: x64-windows-release
+```
+
+## Usage
+
+```yaml
+- uses: johnwason/vcpkg-action@v1
+  with:
+    # The vcpkg packages to build, separated by spaces
+    pkgs: ''
+    # The vcpkg target triplet to use. This must be set. For windows, 
+    # x64-windows-release is recommended if you don't need debug libraries
+    triplet: ''
+    # Extra arguments to pass to vcpkg command (optional)
+    extra-args: ''
+    # Additional string to add to cache key (optional)
+    cache-key: ''
+
+```