Pointer.isnull readonly
The Pointer.isnull property checks if the Pointer is NULL, returning true in this case or false otherwise.
Example
local crt = c.Library()
-- Use the Library instance to define the C function "strstr()"
-- this function takes two arguments of the Z type (const char *)
-- and returns a char* value
crt.strstr = "(ZZ)p"
-- Calls the just defined C function, returning a C Pointer
local result = crt.strstr("Hello LuaRT", "tea")
if result.isnull then
print("The word 'tea' cannot be found in 'Hello LuaRT' string")
end