Mandatory action
Define the preprocessor macro EPS_RTOS_CFG_INCLUDE_H=<posix_macro_header.h> by a compiler argument, e.g. "-DEPS_RTOS_CFG_INCLUDE_H=eps_posix_cfg_windows.h".
Optional
Create a new file <posix_macro_header.h> with the macro definitions.
You may use the sample files eps_posix_cfg_linux.h or
eps_posix_cfg_windows.h.