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+# Parameter mapping
+
+## Parameter map for this CMake project and original Perl-based `Configure`
+
+| Perl `Configure` item | CMake parameter | Notes |
+|-|-|-|
+| `no-<cipher/something>` | `-DOPENSSL_<CIPHER/SOMETHING>=0` | Use capitalized CIPHER name in CMake.<br />`OPENSSL_NO_<CIPHER>` is set automatically. |
+| `enable-cipher/something>`<br />`threads` / `sctp` / `386` | `-DOPENSSL_<CIPHER/SOMETHING>=1`| |
+| `--prefix=` | `-DCMAKE_INSTALL_PREFIX=` | |
+| `--openssldir=` | `-DOPENSSL_OPENSSLDIR=` | Relative to `CMAKE_INSTALL_PREFIX` |
+| `--api=` | `-DOPENSSL_MIN_API_LEVEL=` | |
+| `no-shared static` | `-DBUILD_SHARED_LIBS=OFF` | A series of shared library is built by default.<br />Building shared and static library in one go is not supported by now. |
+| (os/platform) | (automatically detected) | See following OS / Platform mapping |
+| `--cross-compile-prefix=` | `-DCMAKE_TOOLCHAIN_FILE=`<br />(A totally different design) | Typical CMake cross build method are used |
+
+## OS / Platform mapping
+
+| Host | Auto-detected platform name (as if passed to `Configure`) | Notes |
+|-|-|-|
+| Windows x86_64 MSVC with NASM or without ASM | `VC-WIN64A` | |
+| Windows x86_64 MSVC with ASM without NASM | `VC-WIN64A-MASM` | |
+| Windows x86 MSVC | `VC-WIN32` | |
+| Windows x86_64 MinGW | `mingw64` | |
+| Windows x86 MinGW | `mingw` | |
+| Cygwin x86_64 | `Cygwin-x86_64` | |
+| Cygwin x86 | `Cygwin-x86` | Deprecated? |
+| macOS x86_64 | `darwin64-x86_64` | |
+| macOS arm64 | `darwin64-arm64` | |
+| iOS x86_64 | `iossimulator-xcrun` | Distinguishing simulator / actual machine is not done |
+| iOS arm32 | `ios-xcrun` | |
+| iOS arm64 | `ios64-xcrun` | |
+| iOS (unknown architecture) | `iphoneos-cross` | Legacy |
+| Android x86_64 | `android-x86_64` | |
+| Android arm32 | `android-arm` | |
+| Android x86 | `android-x86` | |
+| Android arm64 | `android-arm64` | |
+| Android (unknown architecture) | `android` | Legacy |
+| Linux x86_64 Clang | `linux-x86_64-clang` | |
+| Linux x86_64 (other compiler) | `linux-x86_64` | |
+| Linux x86 Clang | `linux-x86-clang` | |
+| Linux x86 (other compiler) | `linux-x86` | |
+| Linux arm32 | `linux-armv4` | |
+| Linux arm64 | `linux-aarch64` | |
+| Linux (unknown architecture, sizeof pointer equals 8) | `linux-generic64` | |
+| Linux (unknown architecture, sizeof pointer equals 4) | `linux-generic32` | |
+| Any BSD x86_64 | `BSD-x86_64` | |
+| Any BSD x86 | `BSD-x86-elf` | |
+| Any BSD (unknown architecture, sizeof pointer equals 8) | `BSD-generic64` | |
+| Any BSD (unknown architecture, sizeof pointer equals 4) | `BSD-generic32` | |
+| Others | (unknown) | Will be added when supported |