Not root user cannot write file at mounted file system.

Not root user cannot write file at mounted file system. Any command such as `echo` (stdout) and `vi` couldn’t work. But file or director can be create. Besides, `chown`couldn’t work and cause error “operation not permitted”. It is intelligible that the files on iOS having its owner authority.
To protect iSH I am not very willing use root all the time. But the write authority make it hard to write something on USB hard disk or iOS file system. Can you provide some advise to address it?

The issue names no source file, test, or entry point. Start by reproducing writes and chown on a mounted filesystem as a non-root user, comparing file creation with stdout, editor writes, and ownership changes; done means supported mounted filesystems can be written without root or the limitation is clearly documented.

Written by the indexing model from the issue text.