Function gmsh_sys::gmshOptionGetNumber

pub unsafe extern "C" fn gmshOptionGetNumber(
    name: *const c_char, 
    value: *mut f64, 
    ierr: *mut c_int
)

Get the value of a numerical option. name is of the form "category.option" or "category[num].option". Available categories and options are listed in the Gmsh reference manual.