Which lexer do people use?

Hello,

the historical pairing is using Flex with Bison. However, while Bison is
under active development and seems to be a very solid code base, there
isn't much activity on the Flex side https://github.com/westes/flex and
Flex codebase and capabilities show their age.

I recently became aware of RE/flex https://www.genivia.com/reflex.html
which seems very promising. However, it only generates a C++ scanner
which may be (I haven't tried) to retro-fit into existing C projects to,
for example, gain full unicode (in its utf8 encoded form) support.

Has anyone tried to hammer a C++ scanner peg generated by RE/flex into a
C grammar hole generated by Bison?

Which other scanners do people use?

Thank you.

Cheers,
Dan