we can now read c style string arrays

src/lib.rs

@@ -1,7 +1,35 @@
+extern crate ffi_convert;
+extern crate libc;
+
+use ffi_convert::{AsRust, CReprOf, CStringArray};
+use libc::c_char;
+use libc::size_t;
+//use std::ffi::CStr;
+//use std::ffi::CString;
+use std::path::Path;
+//use std::slice;
+
+fn file_exists(file_path: &str) -> bool {
+    return Path::new(file_path).is_file();
+}
+
+#[no_mangle]
+pub extern "C" fn files_exist(f: *const *const c_char, len: size_t) -> () {
+    let files = unsafe {
+        assert!(!f.is_null());
+        CStringArray { data: f, size: len }
+    };
+
+    println!("{:?}", files.as_rust().unwrap());
+    std::mem::forget(files);
+}
+
 #[cfg(test)]
 mod tests {
+    use super::*;
+
     #[test]
     fn it_works() {
-        assert_eq!(2 + 2, 4);
+        assert_eq!(file_exists("/home/nathan/Downloads/cert.sh"), true);
     }
 }