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externals/vcpkg/docs/examples/installing-and-using-packages.md

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+## Installing and Using Packages Example: SQLite
+
+_Note: this old example uses Classic Mode, but most developers will be happier with Manifest Mode. See [Manifest Mode: CMake Example](manifest-mode-cmake.md) for an example of converting to Manifest Mode._
+
+  - [Step 1: Install](#install)
+  - [Step 2: Use](#use)
+    - [VS/MSBuild Project (User-wide integration)](#msbuild)
+    - [CMake (Toolchain file)](#cmake)
+    - [Other integration options](../users/buildsystems/integration.md)
+
+---
+<a name="install"></a>
+## Step 1: Install
+
+First, we need to know what name [SQLite](https://sqlite.org) goes by in the ports tree. To do that, we'll run the `search` command and inspect the output:
+```no-highlight
+PS D:\src\vcpkg> .\vcpkg search sqlite
+libodb-sqlite        2.4.0            Sqlite support for the ODB ORM library
+sqlite3              3.32.1           SQLite is a software library that implements a se...
+
+If your library is not listed, please open an issue at:
+    https://github.com/Microsoft/vcpkg/issues
+```
+Looking at the list, we can see that the port is named "sqlite3". You can also run the `search` command without arguments to see the full list of packages.
+
+Installing is then as simple as using the `install` command.
+```no-highlight
+PS D:\src\vcpkg> .\vcpkg install sqlite3
+Computing installation plan...
+The following packages will be built and installed:
+    sqlite3[core]:x86-windows
+Starting package 1/1: sqlite3:x86-windows
+Building package sqlite3[core]:x86-windows...
+-- Downloading https://sqlite.org/2020/sqlite-amalgamation-3320100.zip...
+-- Extracting source C:/src/vcpkg/downloads/sqlite-amalgamation-3320100.zip
+-- Applying patch fix-arm-uwp.patch
+-- Using source at C:/src/vcpkg/buildtrees/sqlite3/src/3320100-15aeda126a.clean
+-- Configuring x86-windows
+-- Building x86-windows-dbg
+-- Building x86-windows-rel
+-- Performing post-build validation
+-- Performing post-build validation done
+Building package sqlite3[core]:x86-windows... done
+Installing package sqlite3[core]:x86-windows...
+Installing package sqlite3[core]:x86-windows... done
+Elapsed time for package sqlite3:x86-windows: 12 s
+
+Total elapsed time: 12.04 s
+
+The package sqlite3:x86-windows provides CMake targets:
+
+    find_package(unofficial-sqlite3 CONFIG REQUIRED)
+    target_link_libraries(main PRIVATE unofficial::sqlite3::sqlite3))
+
+```
+
+We can check that sqlite3 was successfully installed for x86 Windows desktop by running the `list` command.
+```no-highlight
+PS D:\src\vcpkg> .\vcpkg list
+sqlite3:x86-windows         3.32.1           SQLite is a software library that implements a se...
+```
+
+To install for other architectures and platforms such as Universal Windows Platform or x64 Desktop, you can suffix the package name with `:<target>`.
+```no-highlight
+PS D:\src\vcpkg> .\vcpkg install sqlite3:x86-uwp zlib:x64-windows
+```
+
+See `.\vcpkg help triplet` for all supported targets.
+
+---
+<a name="use"></a>
+## Step 2: Use
+<a name="msbuild"></a>
+#### VS/MSBuild Project (User-wide integration)
+
+The recommended and most productive way to use vcpkg is via user-wide integration, making the system available for all projects you build. The user-wide integration will prompt for administrator access the first time it is used on a given machine, but afterwards is no longer required and the integration is configured on a per-user basis.
+```no-highlight
+PS D:\src\vcpkg> .\vcpkg integrate install
+Applied user-wide integration for this vcpkg root.
+
+All C++ projects can now #include any installed libraries.
+Linking will be handled automatically.
+Installing new libraries will make them instantly available.
+```
+*Note: You will need to restart Visual Studio or perform a Build to update intellisense with the changes.* 
+
+You can now simply use File -> New Project in Visual Studio and the library will be automatically available. For SQLite, you can try out their [C/C++ sample](https://sqlite.org/quickstart.html).
+
+To remove the integration for your user, you can use `.\vcpkg integrate remove`.
+
+<a name="cmake"></a>
+#### CMake (Toolchain File)
+
+The best way to use installed libraries with cmake is via the toolchain file `scripts\buildsystems\vcpkg.cmake`. To use this file, you simply need to add it onto your CMake command line as:  
+`-DCMAKE_TOOLCHAIN_FILE=D:\src\vcpkg\scripts\buildsystems\vcpkg.cmake`.
+
+If you are using CMake through Open Folder with Visual Studio you can define `CMAKE_TOOLCHAIN_FILE` by adding a "variables" section to each of your `CMakeSettings.json` configurations:
+
+```json
+{
+  "configurations": [{
+    "name": "x86-Debug",
+    "generator": "Visual Studio 15 2017",
+    "configurationType" : "Debug",
+    "buildRoot":  "${env.LOCALAPPDATA}\\CMakeBuild\\${workspaceHash}\\build\\${name}",
+    "cmakeCommandArgs": "",
+    "buildCommandArgs": "-m -v:minimal",
+    "variables": [{
+      "name": "CMAKE_TOOLCHAIN_FILE",
+      "value": "D:\\src\\vcpkg\\scripts\\buildsystems\\vcpkg.cmake"
+    }]
+  }]
+}
+```
+*Note: It might be necessary to delete the CMake cache folder of each modified configuration, to force a full regeneration. In the `CMake` menu, under `Cache (<configuration name>)` you'll find `Delete Cache Folders`.*
+
+Now let's make a simple CMake project with a main file.
+```cmake
+# CMakeLists.txt
+cmake_minimum_required(VERSION 3.0)
+project(test)
+
+find_package(unofficial-sqlite3 CONFIG REQUIRED)
+
+add_executable(main main.cpp)
+
+target_link_libraries(main PRIVATE unofficial::sqlite3::sqlite3)
+```
+```cpp
+// main.cpp
+#include <sqlite3.h>
+#include <stdio.h>
+
+int main()
+{
+    printf("%s\n", sqlite3_libversion());
+    return 0;
+}
+```
+
+Then, we build our project in the normal CMake way:
+```no-highlight
+PS D:\src\cmake-test> mkdir build 
+PS D:\src\cmake-test> cd build
+PS D:\src\cmake-test\build> cmake .. "-DCMAKE_TOOLCHAIN_FILE=D:\src\vcpkg\scripts\buildsystems\vcpkg.cmake"
+    // omitted CMake output here //
+-- Build files have been written to: D:/src/cmake-test/build
+PS D:\src\cmake-test\build> cmake --build .
+    // omitted MSBuild output here //
+Build succeeded.
+    0 Warning(s)
+    0 Error(s)
+
+Time Elapsed 00:00:02.38
+PS D:\src\cmake-test\build> .\Debug\main.exe
+3.15.0
+```
+
+*Note: The correct sqlite3.dll is automatically copied to the output folder when building for x86-windows. You will need to distribute this along with your application.*
+
+##### Handling libraries without native cmake support
+
+Unlike other platforms, we do not automatically add the `include\` directory to your compilation line by default. If you're using a library that does not provide CMake integration, you will need to explicitly search for the files and add them yourself using [`find_path()`][1] and [`find_library()`][2].
+
+```cmake
+# To find and use catch
+find_path(CATCH_INCLUDE_DIR catch.hpp)
+include_directories(${CATCH_INCLUDE_DIR})
+
+# To find and use azure-storage-cpp
+find_path(WASTORAGE_INCLUDE_DIR was/blob.h)
+find_library(WASTORAGE_LIBRARY wastorage)
+include_directories(${WASTORAGE_INCLUDE_DIR})
+link_libraries(${WASTORAGE_LIBRARY})
+
+# Note that we recommend using the target-specific directives for a cleaner cmake:
+#     target_include_directories(main ${LIBRARY})
+#     target_link_libraries(main PRIVATE ${LIBRARY})
+```
+
+[1]: https://cmake.org/cmake/help/latest/command/find_path.html
+[2]: https://cmake.org/cmake/help/latest/command/find_library.html