(grep) Regex to match non-ASCII characters ?

Below code will match a single non-ASCII character:

[^\x00-\x7F]

Refer this link for PCRE (Perl-Compatible Regular Expression).

Use the POSIX shorthands:

1. [[:ascii:]] -it will matches a single ASCII char.
2. [^[:ascii:]] – it will matches a single non-ASCII char.

[^[:print:]] it will satisfy our needs.

Try this link for : Unicode Regular Expressions:

\p{Control}: an ASCII 0x00..0x1F or Latin-1 0x80..0x9F control character.