diff --git a/verify_ecdh.c b/verify_ecdh.c
index 046aeb0..da073f9 100644
--- a/verify_ecdh.c
+++ b/verify_ecdh.c
@@ -2,9 +2,42 @@
 
 #include <stdio.h>
 #include <string.h>
+
+#if __AVR__
+
+int RNG(uint8_t *p_dest, unsigned p_size)
+{
+    /* TODO */
+    return 0;
+}
+
+#else
+
 #include <unistd.h>
 #include <fcntl.h>
 
+int RNG(uint8_t *p_dest, unsigned p_size)
+{
+    static int l_randfd = -1;
+    if(l_randfd == -1)
+    {
+        l_randfd = open("/dev/urandom", O_RDONLY);
+        if(l_randfd == -1)
+        {
+            printf("No access to urandom\n");
+            return 0;
+        }
+    }
+    if(read(l_randfd, p_dest, p_size) != (int)p_size)
+    {
+        printf("Failed to get random bytes.\n");
+        return 0;
+    }
+    return 1;
+}
+
+#endif /* TARGET_ARCH_AVR */
+
 void vli_print(uint8_t *p_vli, unsigned int p_size)
 {
     while(p_size)
@@ -14,18 +47,6 @@ void vli_print(uint8_t *p_vli, unsigned int p_size)
     }
 }
 
-int randfd;
-
-int RNG(uint8_t *p_dest, unsigned p_size)
-{
-    if(read(randfd, p_dest, p_size) != (int)p_size)
-    {
-        printf("Failed to get random bytes.\n");
-        return 0;
-    }
-    return 1;
-}
-
 int main()
 {
     int i;
@@ -38,14 +59,7 @@ int main()
     
     uint8_t l_secret1[ECC_BYTES];
     uint8_t l_secret2[ECC_BYTES];
-    
-    randfd = open("/dev/urandom", O_RDONLY);
-    if(randfd == -1)
-    {
-        printf("No access to urandom\n");
-        return -1;
-    }
-    
+
     ecc_set_rng(&RNG);
     
     printf("Testing 256 random private key pairs\n");