[kinkdr]

IMHO it is OK if you are only going to call a few simple one, but for calling a few hundred complex ones (callbacks with variable argument list, etc..), it becomes a bit cumbersome.

BTW I am not implying that is Rust's fault, actually I can't think a syntax that would make it less verbose, and I am a huge Rust fan.

[Manishearth]

Not really, there are tools that can take C header files and spit out bindings. Rust also supports vararg C functions even though Rust itself doesn't support varargs. Writing safe Rust wrappers around these unsafe C bindings can sometimes be tedious, but this isn't worse than using C directly (which is inherently unsafe).

[kinkdr]

I didn't say it is not supporting them. I said that is a bit cumbersome to have to write the shims for them.

I wasn't aware of the tools that do this automatically. Just found one and it looks promising.

[Manishearth]

Yeah, my point was that thin shims are free, and "thick" safe shims take effort but as far as comparing with pure C is concerned you only need to compare the cost of thin shims. C doesn't have safety so the concept of a thick, safe shim is nonexistant.

[ktRolster]

actually I can't think a syntax that would make it less verbose.

something like C::function_from_c() is one option

[kibwen]

For very extensive C APIs like this (Lua, GTK, etc.) we typically see people create thin, Rust-friendly wrappers to reduce the amount of manual API calls that need to be written out.