[Help-glpk] Find solutions without objective function

[jordan]

Hello,
I'm using GLPK (with glpsol and the C API).
And I want to know if I can generate all the solution of a problem, and
not the most optimized. Is it possible to have all solutions of a
problem without an objective function ? Just using the constraints.
For example, for a Sudoku, have all the different solutions.

Thanks.

Jordan.