Library code, especially stdlib, is usually the bottom of the abstraction chain and rarely performs fallible operations like IO. It’s the one originating the er

Library code, especially stdlib, is usually the bottom of the abstraction chain and rarely performs fallible operations like IO. It’s the one originating the errors. The issue is that application code usually has several layers between the end-user and the fundamental operations like Read()/Write(). Bookkeeping errors through all these layers is a chore. You can skip the layers but then you get spaghetti.