A error when running dynare model

[Iceicecool]

Hi
When I am running a dynare model, there seems be a error. Is there any who can help me with this? Thank you so much.
var s k c Ec u ;

varexo epsilon;

parameters rho pk y pc beta r sigma ;


rho=0.7;
pk=1;
sigma=0.1;
y=1;
pc=1.5;
beta = 0.5;
r=0.8;



model(linear);
Ec = c(+1);
c=Ec-r+ u;
k=(1-sigma)*k(-1)+s+u;
s=(rho-sigma)*pk*k+y-pc*c;
u=epsilon;

end;


shocks;
var epsilon;
stderr 1;
end;

steady;
stoch_simul;

!!!
ERROR: project.mod: line 25, cols 6-10: To use an external function (c) within the model block, you must first declare it via the external_function() statement.

Error using dynare (line 174)
DYNARE: preprocessing failed

[jpfeifer]

With your mod-file, I get a different error message. The one you have usually appears when you did not declare c as a variable.
The problem I face is that the model is not properly linearized. In the second equation, there is a constant term r.