APIs, libraries, and code

Diomidis Spinellis, a professor in the Department of Management Science and Technology at the Athens University of Economics and Business, suggests some points to consider while using APIs, libraries and writing own code. If some alternatives come as external libraries, one should start by looking at the licensing terms. Many offerings might be available as open source software, so integrating GPL-licensed code with a product distributed without its source code will get them into trouble. Libraries should be configured with sensible defaults that allow them to work faultlessly under all conditions. If the system is multithreaded, users must examine whether the library is compatible with such a setting. Error handling is another area of disagreements. A function can signal an error by returning a negative value, a false value, or by triggering an exception. The user needs to balance the functionality the library provides against its dependencies.