anchor.diff:  echo -v^|--vs-version      --Set Visual Studio version to configure. Must be one of: vs2015, vs2017, vs2019
   echo -p^|--pthreads-home   --Set pthreads-win32 home directory
   echo -w^|--pcap-sdk        --Set WinPcap/Npcap SDK directory
  +echo -z^|--zstd-sdk        --Set ZStd SDK directory
   echo -h^|--help            --Display this help message and exits. No further actions are performed
   echo.
   :: done printing, exit
  
positive.code: :CASE-w
  :CASE--pcap-sdk
      :: this argument must have a parameter. If no parameter was found goto GETOPT_REQUIRED_PARAM and exit
      if "%2"=="" goto GETOPT_REQUIRED_PARAM %1
      :: verify the WinPcap/Npcap SDK dir provided by the user exists. If not, exit with error code 3, meaning ask the caller to exit the script
      if not exist %2\ call :GETOPT_ERROR "WinPcap/Npcap SDK directory '%2' does not exist" & exit /B 3
      :: if all went well, set the PCAP_SDK_HOME variable with the directory given by the user
      set PCAP_SDK_HOME=%2
      :: notify GETOPT this switch has a parameter
      set HAS_PARAM=1
      :: exit ok
  
negative.code: :CASE-v
  :CASE--vs-version
      :: this argument must have a parameter. If no parameter was found goto GETOPT_REQUIRED_PARAM and exit
      if "%~2"=="" goto GETOPT_REQUIRED_PARAM %1
      :: verify the VS version provided is one of the supported versions
      if "%2" NEQ "vs2015" if "%2" NEQ "vs2017" if "%2" NEQ "vs2019" call :GETOPT_ERROR "Visual Studio version must be one of: vs2015, vs2017, vs2019" & exit /B 3
      :: if all went well, set the VS_VERSION variable
  