How to dynamically load a Rust library in C?

Question

I'm trying to dynamically link a Rust .so library with a C program in Linux with gcc. Using only dlopen and dlclose results in no errors, but I get a segmentation fault with the following code:

char * (*my_function)(char *);
char *my_input_string = "foo";

//...abbreviated code...

my_function = dlsym(handle, "my_function");
char *my_output_string = (*my_function)(my_input_string);

I'm using gcc -g foo.c -ldl -o foo to compile, if that matters.

I know that it's finding the symbol because I used #[no_mangle] in the rust library and the my_function pointer is not null

@malbarbo It's `pub extern "C" fn my_function(my_string: *const c_char) -> *const c_char` — Alex Lamson, Jul 01 '16 at 19:34

score 0 · Accepted Answer · answered Jul 01 '16 at 20:04

0

I ran it through gdb and it turns out the library was trying to call a function in the calling program that didn't exist.

answered Jul 01 '16 at 20:04

Alex Lamson

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How to dynamically load a Rust library in C?

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