The function pointer-element-type-p
returns true if the element type of the foreign object pointed to by pointer has the same underlying type as type.
(setq point (fli:allocate-foreign-object :type :int))
=>
=> #<Pointer to type :INT = #x007F3970>
(fli:pointer-element-type-p point :signed)
->
t
LispWorks Foreign Language Interface User Guide and Reference Manual - 29 Sep 2017