Add c_libcurl.exs

.gitignore

@@ -1 +1,2 @@
 checksum-Elixir.RustlerPrecompilationExample.Native.exs
+_build

c_libcurl.exs

@@ -0,0 +1,60 @@
+Mix.install([
+  {:c, github: "wojtekmach/c"}
+])
+
+defmodule Curl.MixProject do
+  use Mix.Project
+
+  def project do
+    [
+      app: :curl,
+      version: "1.0.0"
+    ]
+  end
+end
+
+defmodule Main do
+  def main do
+    Curl.test()
+  end
+end
+
+defmodule Curl do
+  use C, compile: "-lcurl"
+
+  # Based on https://curl.se/libcurl/c/simple.html
+
+  defc(:test, 0, ~S"""
+  #include <curl/curl.h>
+
+  static ERL_NIF_TERM test(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+  {
+    CURL *curl;
+    CURLcode res;
+
+    curl = curl_easy_init();
+
+    if (!curl) {
+      enif_raise_exception(env, enif_make_string(env, "could not init curl", ERL_NIF_LATIN1));
+      return -1;
+    }
+
+    curl_easy_setopt(curl, CURLOPT_URL, "https://httpbin.org/json");
+
+    /* Perform the request, res will get the return code */
+    res = curl_easy_perform(curl);
+
+    /* Check for errors */
+    if (res != CURLE_OK) {
+      fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
+    }
+
+    /* always cleanup */
+    curl_easy_cleanup(curl);
+
+    return enif_make_atom(env, "ok");
+  }
+  """)
+end
+
+Main.main()