how to clear a variable in a C interface

[Collette Yann]

Hello,

I am writing a C interface. I would like to clean up a variable in that 
C interface, but I don't know how to remove it.

GetRhsVar(1, "d", &m_var, &n_var, &l_var);

....

ClearRhsVar(&m_var, &n_var, &l_var); // I'm looking for this kind of 
function which will remove the variable l_var from the stack.

YC