Add call to grib_samples_path in examples/C

examples/C/set_data.c

@@ -36,6 +36,8 @@ int main(int argc, char** argv)
     /* see where that is).  The default sample path can be changed by       */
     /* setting the environment variable GRIB_SAMPLES_PATH                   */
     const char* sample_filename = "regular_ll_pl_grib1";
+    /* Here is how you can get the samples path */
+    const char* samples_path = grib_samples_path(NULL);
     grib_handle *h = NULL;
     double d,e;
     long count;