How to setup ''specular'' in material with c++

hi everyone. In material there have three Custom Settings’ tool : specular、reflection and transparency I want to control specular use c++ code.(Red circle in picture which is named " Gl ")

I can use m_transparency& m_reflectivity in “opennurbs_material.h” to control it’s proportion and both work.Also I can change specular’s color but can’t control specular’s proportion with m_shine or SetShine(). It’s there have any code can do it ?

It’s m_shine, but read the comments carefully. M_shine runs from 0-max_shine

Oh! I set a number >1 and than it’s work . sorry i thought it’s as same as other two parameter.
thank you.