No, that's not what re-entrant means. A re-entrant function can be called multiple times at the same time. That could be from different threads or from an inte

No, that's not what re-entrant means. A re-entrant function can be called multiple times at the same time. That could be from different threads or from an interrupt handler. It can even come up in single-threaded code: you call function A() which internally calls B() which results in a nested call to A(). If A is re-entrant that's safe.