Go Developers Warned Against Using fmt.Println for Error Output Handling

A technical guide highlights a common mistake Go developers make by using fmt.Println for error messages, which incorrectly writes to stdout instead of stderr. On Linux and Unix systems, the kernel assigns three file descriptors — stdin, stderr, and stdout — each serving a distinct purpose in shell environments. Using Go's built-in println() or print() functions is also discouraged, as they write to stderr and are considered temporary debugging tools that may be removed in future versions. The recommended approach is to use fmt.Fprintln() combined with the os package, which allows developers to explicitly direct output to the correct stream. For production-grade applications, the guide further suggests dedicated logging libraries such as log, slog, or errors for robust error handling.