ed.cpp: In function `int main()': ed.cpp:29: warning: assignment to non-pointer type `char' from NULL ed.cpp:29: warning: argument to non-pointer type `char' from NULL ed.cpp:36: warning: assignment to non-pointer type `char' from NULL ed.cpp:36: warning: argument to non-pointer type `char' from NULL ed.cpp:48: warning: assignment to non-pointer type `char' from NULL ed.cpp:48: warning: argument to non-pointer type `char' from NULL ed.cpp:52: warning: assignment to non-pointer type `char' from NULL ed.cpp:52: warning: argument to non-pointer type `char' from NULL