While that makes them the same stream, it doesn't actually solve the problem. Many systems will write to stdout buffered, but stderr unbuffered, so that writes

While that makes them the same stream, it doesn't actually solve the problem. Many systems will write to stdout buffered, but stderr unbuffered, so that writes are visible when the program crashes. Redirecting streams at the shell level doesn't stop application level buffering ruining your day. Having said that, GP's request is pretty niche, it's only useful when the program uses stdout (not a gui, web etc) and is doing work that might write to stderr while it's writing to stdout (so no summary report generators, long running physics simulations etc)