Building-with-CMake.md

\page netCDF-CMake Build Instructions for netCDF-C using CMake


# Overview

Starting with netCDF-C 4.3, we are happy to announce the inclusion of CMake support.  CMake will allow for building netCDF on a wider range of platforms, include Microsoft Windows with Visual Studio.  CMake support also provides robust unit and regression testing tools.  We will also maintain the standard autotools-based build system in parallel.

In addition to providing new build options for netCDF-C, we will also provide pre-built binary downloads for the shared versions of netCDF for use with Visual Studio.  

# Requirements
The following packages are required to build netCDF-C using CMake.

* netCDF-C Source Code
* CMake version 2.9+
* Optional Requirements:
        * HDF5 Libraries for netCDF4/HDF5 support.
        * libcurl for DAP support.

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# The CMake Build Process

There are four steps in the Build Process when using CMake

1. Configuration: Before compiling, the software is configured based on the desired options.
2. Building: Once configuration is complete, the libraries are compiled.
3. Testing: Post-build, it is possible to run tests to ensure the functionality of the netCDF-C libraries.
4. Installation: If all tests pass, the libraries can be installed in the location specified during configuration.

For users who prefer pre-built binaries, installation packages are available at \ref winbin

## Configuration

The output of the configuration step is a project file based on the appropriate configurator specified.  Common configurators include:

* Unix Makefiles
* Visual Studio
* CodeBlocks
* ... and others

### Common CMake Options

| **Option** | **Autotools** | **CMake** |
| :------- | :----: | :-----: |
Specify Install Location | --prefix=PREFIX | -D"CMAKE\_INSTALL\_PREFIX=PREFIX"
Enable/Disable netCDF-4 | --enable-netcdf-4<br>--disable-netcdf-4 | -D"ENABLE\_NETCDF\_4=ON" <br> -D"ENABLE\_NETCDF\_4=OFF"
Enable/Disable DAP | --enable-dap <br> --disable-dap | -D"ENABLE\_DAP=ON" <br> -D"ENABLE\_DAP=OFF"
Enable/Disable Utilities | --enable-utilities <br> --disable-utilities | -D"BUILD\_UTILITIES=ON" <br> -D"BUILD\_UTILITIES=OFF"
Specify shared/Static Libraries | --enable-shared <br> --enable-static | -D"BUILD\_SHARED\_LIBS=ON" <br> -D"BUILD\_SHARED\_LIBS=OFF"
Enable/Disable Tests | --enable-testsets <br> --disable-testsets | -D"ENABLE\_TESTS=ON" <br> -D"ENABLE\_TESTS=OFF"

## Building

The compiler can be executed directly with 'make' or the appropriate command for the configurator which was used.  

> \> make

Building can also be executed indirectly via cmake:

> \> cmake --build [Build Directory]

## Testing

Testing can be executed several different ways:

> \> make test
or
> \> ctest
or
> \> cmake --build [Build Directory] --target test

## Installation

Once netCDF has been built and tested, it may be installed using the following commands:

> \> make install
or
> \> cmake --build [Build Directory] --target install