In order to use the TiGL library in a C program, you have to link against the TiGL as well as the TiXI library. The TiXI (TiXI Xml Interface) is used to read in the XML-based CPACS files. It can be obtained from the project site http://github.com/DLR-SC/tixi. In addition to the libraries itself, one needs to include the corresponding header files:

#include "tigl.h" 
#include "tixi.h"

For example, to open a CPACS configuration, one can use

TixiDocumentHandle tixiHandle;
TiglCPACSConfigurationHandle tiglHandle;
tixiOpenDocument("aFileName", &tixiHandle);
tiglOpenCPACSConfiguration(tixiHandle, "aConfigurationUID", &tiglHandle);

For more details and for the usage from Python or Matlab, see the examples in the

TIGL_INSTALL_DIR/share/doc/tigl3/examples

directory.