DcpClient

DcpClient is a Qt-based C++ library for the Device Communication Protocol (DCP), primarily used at the GREGOR solar telescope on Tenerife.

This package consists of

• libDcpClient: The DCP C++ library
• dcpterm: A GUI for communicating with DCP devices
• dcphub: A basic implementation of a DCP server

as well as various other tools and examples.

Build requirements

• Qt 4.7 or Qt 5
• CMake 2.8.12 or newer

How to install

Extract the source archive (or checkout the Git repository). Change into the dcpclient directory and create a build subdirectory. Change into the build directory and run cmake, make and make install.

cd dcpclient
mkdir build

cd build
cmake .. \
    -DCMAKE_BUILD_TYPE=Release \
    -DCMAKE_INSTALL_PREFIX=/opt/dcpclient \
    -DBUILD_TOOLS=ON

make
make install

For the make install command you need to have write access to the directory specified by the CMAKE_INSTALL_PREFIX option. You can, for example, use sudo make install, or create the destination directory manually and make sure that your (non-root) user has access to it (recommended).

Build options

There are a number of CMake build options available. These options can be set using -DOPTION_NAME=VALUE when running cmake, or by using the CMake GUI cmake-gui (Qt-based) or ccmake (ncurses-based).

• CMAKE_BUILD_TYPE: CMake build type (e.g. "Release" or "Debug"; default: "")
• CMAKE_INSTALL_PREFIX: Installation base directory (Linux default: "/usr/local")
• BUILD_TOOLS: Build utility programs dcpterm, dcphub, and dcpsend (default: OFF)
• BUILD_EXAMPLES: Build example programs dcpdump, dcplisten, dcptime (default: OFF)
• BUILD_USE_QT4: Use Qt4 even if Qt5 is installed (default: OFF)
• BUILD_STATIC_LIBRARY: Build a static DcpClient library (default: OFF)
• INSTALL_STATIC_LIBRARY: Install static library if static build was enables (default: OFF)
• BUILD_DOCUMENTATION: Build Doxygen documentation (default: OFF)
• INSTALL_EXAMPLE_SOURCES: Install example source code (default: OFF)

Example configurations

Below are some examples for configuring the build with the cmake command. These examples assume that you already changed to the dcpclient/build directory as described above. For compiling and installing you still need to run make and make install after using cmake. If you are trying out different builds in the same build directory, it might be necessary to run make clean first, and to delete the CMakeCache.txt before re-executing the cmake command.

Only build and install the library

The following will only build the DcpClient library, without any utility programs. The header files and the shared library will be installed using the default installation prefix (e.g. /usr/local on Linux).

cmake .. -DCMAKE_BUILD_TYPE=Release

Build tools and shared library, install to /opt/dcpclient

This is a typical way of building the shared DcpClient library together with dcpterm, dcphub and dcpsend, and install it to /opt/dcpclient.

cmake .. \
    -DCMAKE_BUILD_TYPE=Release \
    -DCMAKE_INSTALL_PREFIX=/opt/dcpclient \
    -DBUILD_TOOLS=ON

On Unix-like systems RPATH is used by default. If you want to make the installation directory relocatable, you can use the CMAKE_INSTALL_RPATH option with $ORIGIN on Linux or @loader_path on MacOS. To make the above example relocatable on Linux you would write:

cmake .. \
    -DCMAKE_BUILD_TYPE=Release \
    -DCMAKE_INSTALL_PREFIX=/opt/dcpclient \
    -DCMAKE_INSTALL_RPATH='$ORIGIN/../lib' \
    -DBUILD_TOOLS=ON

Note that the single quotation marks in '$ORIGIN/../lib' are important to prevent the shell from interpreting $ORIGIN as a variable.

Statically build tools and examples only, install to build directory

The following example builds all executables (tools and examples) and links statically against the DcpClient library. In this case the programs do not depend on a shared DcpClient library, which can be useful if the library is not needed by any other application.

cmake .. \
    -DCMAKE_BUILD_TYPE=Release \
    -DCMAKE_INSTALL_PREFIX="${PWD}/install" \
    -DBUILD_TOOLS=ON \
    -DBUILD_EXAMPLES=ON \
    -DBUILD_STATIC_LIBRARY=ON

With the command above the executables are installed to the build/install directory when running make install.

Note: If you want to copy the statically linked executables to a different directory, you should use the binaries from the build/install/bin directory, not the binaries that are created in the root of the build directory.