That's a valid concern, but personally I wouldn't expect a tool like this to support anything beyond the POSIX standard switches. For "cat", POSIX only specifie

That's a valid concern, but personally I wouldn't expect a tool like this to support anything beyond the POSIX standard switches. For "cat", POSIX only specifies a single switch: "-u", which enables unbuffered output. I've never used that switch before, and it's a no-op in both GNU cat and shelljs.