How to: Building on Windows
To start with, you need MS Visual Studio (C/C++). The free community edition works well.

Then, install git, and make sure it works from a DevStudio command prompt:

```
git
```

#### Using CMake

`czmq` requires `libzmq`, so we need to build `libzmq` first. For `libzmq`, you can optionally use [libsodium](https://github.com/jedisct1/libsodium) as the curve encryption library. So we will start from building `libsodium` in the following (and you can bypass the building of `libsodium` if you are ok with libzmq's default curve encryption library):
```
git clone --depth 1 -b stable https://github.com/jedisct1/libsodium.git
cd libsodium\builds\msvc\build
buildall.bat
cd ..\..\..\..
```
Once done, you can find the library files under `libsodium\bin\
\
\
\
`.

Here, the `
` is the platform toolset you are using: `v100` for `VS2010`, `v140` for `VS2015`, `v141` for `VS2017`, etc.

```
git clone https://github.com/zeromq/libzmq.git
cd libzmq
mkdir build
cd build
cmake .. -DBUILD_STATIC=OFF -DBUILD_SHARED=ON -DZMQ_BUILD_TESTS=ON -DWITH_LIBSODIUM=ON -DCMAKE_INCLUDE_PATH=..\libsodium\src\libsodium\include -DCMAKE_LIBRARY_PATH=..\libsodium\bin\Win32\Release\
\dynamic -DCMAKE_INSTALL_PREFIX=C:\libzmq
cmake --build . --config Release --target install
cd ..\..\
```
`-DWITH_LIBSODIUM=ON` is necessary if you want to build `libzmq` with `libsodium`. `CMAKE_INCLUDE_PATH` option tells `libzmq` where to search for `libsodium`'s header files. And the `CMAKE_LIBRARY_PATH` option tells where to search for libsodium library files. If you don't need `libsodium` support, you can omit these three options.

`-DCMAKE_INSTALL_PREFIX=C:\libzmq` means we want to install `libzmq` into the `C:\libzmq`. You may need to run your shell with administrator privilege in order to write to the system disk.

Now, it is time to build `czmq`:
```
git clone https://github.com/zeromq/czmq.git
cd czmq
mkdir build
cd build
cmake .. -DCZMQ_BUILD_SHARED=ON -DCZMQ_BUILD_STATIC=OFF -DCMAKE_PREFIX_PATH=C:\libzmq
cmake --build . --config Release
```
Remember that we install `libzmq` to `C:\libzmq` through specifying `-DCMAKE_INSTALL_PREFIX=C:\libzmq` in the previous step. We here use `-DCMAKE_PREFIX_PATH=C:\libzmq` to tell `czmq` where to search for `libzmq`.

That is not the whole story. We didn't mention the building of `libcurl`, `lz4`, `libuuid` and other `czmq` optional libraries above. In fact, to build all of these optional libraries successfully is really tricky. Please refer issue [#1972](https://github.com/zeromq/czmq/issues/1972) for more details.

#### Using MSBuild (Out of date, may not work now!)

```
    git clone --depth 1 -b stable https://github.com/jedisct1/libsodium.git
    cd libsodium\builds\msvc\build
    buildall.bat
    cd ..\..\..\..

    :: if libsodium is on disk, the Windows build of libzmq will automatically use it
    git clone https://github.com/zeromq/libzmq.git
    cd libzmq\builds\msvc
    configure.bat
    cd build
    buildall.bat
    cd ..\..\..\..

    git clone https://github.com/zeromq/czmq.git
    cd czmq\builds\msvc
    configure.bat
    cd build
    buildall.bat
    cd ..\..\..\..
```

Let's test by running `czmq_selftest`:

```
   czmq>dir/s/b czmq_selftest.exe
   czmq\builds\msvc\vs2013\DebugDEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\DebugLEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\DebugSEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\ReleaseDEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\ReleaseLEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\ReleaseSEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\x64\DebugDEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\x64\DebugLEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\x64\DebugSEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\x64\ReleaseDEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\x64\ReleaseLEXE\czmq_selftest.exe
   czmq\builds\msvc\vs2013\x64\ReleaseSEXE\czmq_selftest.exe

    :: select your choice and run it
    czmq\builds\msvc\vs2013\x64\ReleaseDEXE\czmq_selftest.exe
```