> That said, C is not a great glue language: - Zero terminated strings are only used in C so every other language needs to do a copy to pass a string to C, even C++ (for string_view at least).

I don't think that's what he's talking about. No matter what glue you had, you need to pass NUL terminated strings to C code that uses NUL terminated strings.

The glue interface does not require any such thing though.

> A lack of fat pointers means that buffers need to pass their pointer and length separately, which is awkward, or use a custom struct which other languages will know nothing about.

Again passing things between two languages will always necessitate that. One language might have a different fat pointer implementation than another.

And the nice thing about glue code is that it can be easily automatically generated calling wrappers so "awkward" does not come into it - you change one language's data types into another's.

> - It has no standardized error handling mechanism to help with writing automatic wrappers on the other language endpoints. - It has no modules or namespacing.

I don't see how this matters for the interface glue. You can define the error handling with it how you like. You put it in your language's namespaces and modules.