The C function you linked calls _Fork, which calls __wasi_proc_fork, which calls __imported_wasix_32v1_proc_fork, which is the 'proc_fork' import in the 'wasix_32v1' module. The question is, what JavaScript function is provided for this proc_fork import when instantiating a WebAssembly module using WASIX? From what I understand about the WebAssembly JavaScript API, such a function is impossible to implement, which is why I'm curious how it was done here.