I'm not super confident but I think the stdlib flags are a POSIX implementation. However, POSIX is not what most people are used to. For example, POSIX says f

I'm not super confident but I think the stdlib flags are a POSIX implementation. However, POSIX is not what most people are used to. For example, POSIX says flags/options come before arguments but most Linux shells allow you to put the flags/options after arguments as well, e.g. `ls ~ -lh`.