Rust String can contain null bytes! Rust uses explicit string lengths. Agree though that most OS wouldn't be able to pass null bytes in arguments though.
>>adastr+(OP)
Right, but it can't contain invalid UTF-8, which is valid in both command-line parameters and in filenames on Linux, FreeBSD, and other normal Unixes. See my link above for a demonstration of how this causes bugs in Rust programs.