Foreign function interface (FFI)

mu can call native libraries via dlopen, dlsym, and dlcall, or use the higher-level ffi.fn helper for constant bindings.

Example

import "ffi"

puts := ffi.fn("/usr/lib/libSystem.B.dylib", "puts", "i32", ["cstr"])
puts("hello from mu")

Notes

• Signatures are explicit (i8, i16, i32, i64, u8, u16, u32, u64, ptr, cstr, void).
• Dynamic signatures are supported in the VM; native builds require constants.
• Errors are returned as values you can inspect.

See docs/Specification.md for full FFI rules.

Next steps

• Start with the language tour for syntax basics.
• Read the runtime guide for VM/native constraints.
• Explore the standard library modules that build on FFI.