6 Managing Extended Runtime License Information

Extended runtime systems need to have a license available at runtime. This license can be embedded in the extended runtime executable or located in a separate file. The following describes the steps needed in order to enter the license information. The example assumes that you are familiar with the procedure for building runtime systems. See The Application Builder in the SICStus Prolog Manual for details.

Suppose that you have been provided with the following license information:

Dear SICStus Prolog customer,

Your extended runtime license information for platform 'PLATFORM' is as follows:

Site name:          MySite
License code:       a111-b222-c333-d444-e444
Expiration date:    permanent

Corresponding to a file 'extended_license.pl' with the following contents:
%% LICENSE BEGIN
site('MySite').
product('extended_runtime_sicstusMAJOR.MINOR_PLATFORM',
       'permanent',
       'a111-b222-c333-d444-e444').
%% LICENSE END

Please note: The license information differs between SICStus versions and platforms. The PLATORM is one of win32 (for Microsoft Windows), linux, darwin (for Apple macOS), or solaris. The MAJOR.MINOR is the major and minor version of SICStus, currently 4.6.

Following is a list of common tasks.

• Making the license available to the development system.

  Create a file extended_license.pl with the contents specified in the email, that is:

  %% LICENSE BEGIN
  site('MySite').
  product('extended_runtime_sicstusMAJOR.MINOR_PLATFORM',
         'permanent',
         'a111-b222-c333-d444-e444').
  %% LICENSE END
  

  This file can be located anywhere, e.g. in the folder containing your source code.

• Building an Extended Runtime System using spld which embeds license information from the above file:

  % spld -E --license-file ./extended_license.pl […]
  

  This will read the license information and embed the information in the created executable. No separate license file will be needed at runtime. This is the preferred method. This method can be used also to create an all-in-one executable; see All-in-one Executables in the SICStus Prolog Manual.

  On UNIX platforms, it is possible to install the license information using the splm tool so that you do not need create the file extended_license.pl and pass it to spld. However, a separate license file may be needed anyway if the license cannot be embedded; see below.

• Building an Extended Runtime System which does not embed license information.

  The resulting runtime system will need a way to find the license file at runtime. This variant is useful when the executable is not built with spld, e.g. when builing a DLL (Windows) or DSO (UNIX):

  % spld -E --no-embed-license […]
  

  The resulting executable will produce output similar to the following if it cannot find the license file:

  License error:
  License file not found! […]
  

• Ensuring that the license information is available at runtime.

  If the license information has been embedded, then no special steps are needed. Otherwise, you need to distribute the license file along with the runtime system. To make the license file available it should be located in the library folder and named license.pl. That is, copy extended_license.pl as created above into the file library/license.pl in the folder tree available at runtime. See Runtime Systems on Target Machines in the SICStus Prolog Manual for details. Also see Locating the License Information in the SICStus Prolog Manual for additional ways of making the license information available.

• Understanding steps performed by spld. As usual, you can use:

  % spld --verbose --keep […]
  

  in order to see exactly what steps are performed by spld. This is useful if you want to embed the license but need to build the executable manually, instead of using spld.