Part of the reason is standard options, as mentioned elsewhere in this thread: https://news.ycombinator.com/item?id=5520962 https://news.ycombinator.com/item?id

Part of the reason is standard options, as mentioned elsewhere in this thread: https://news.ycombinator.com/item?id=5520962 https://news.ycombinator.com/item?id=5520962 Another part of the reason is that GNU code, historically, tried on purpose to look different at the source code level from other Unix systems, to reduce the possibility of accusations of illegal copying.