diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 0000000..9729ef4
Binary files /dev/null and b/.DS_Store differ
diff --git a/protobuf.c b/protobuf.c
index f76e232..061c6d3 100644
--- a/protobuf.c
+++ b/protobuf.c
@@ -33,11 +33,13 @@ static int write_num(FILE* fp, uint32_t n) {
 }
 
 SIMPLE_PB* get_pb(FILE* fp) {
+    uint32_t init_pos = ftell(fp);
     uint32_t struct_len = read_num(fp);
     if(struct_len > 1) {
         SIMPLE_PB* spb = malloc(struct_len + sizeof(uint32_t));
         if(spb) {
-            spb->len = struct_len;
+            spb->struct_len = struct_len;
+            spb->real_len = 0;
             char* p = spb->target;
             char* end = p + struct_len;
             memset(p, 0, struct_len);
@@ -47,6 +49,7 @@ SIMPLE_PB* get_pb(FILE* fp) {
                 fread(p, data_len, 1, fp);
                 p += offset;
             }
+            spb->real_len = ftell(fp) - init_pos;
             return spb;
         }
     }
diff --git a/simple_protobuf.h b/simple_protobuf.h
index cab24b0..f730b4c 100644
--- a/simple_protobuf.h
+++ b/simple_protobuf.h
@@ -4,7 +4,7 @@
 #include <stdint.h>
 
 struct SIMPLE_PB {
-    uint32_t len;
+    uint32_t struct_len, real_len;
     char target[];
 };
 typedef struct SIMPLE_PB SIMPLE_PB;
diff --git a/test.c b/test.c
index 284ae51..13eeeb0 100644
--- a/test.c
+++ b/test.c
@@ -34,6 +34,7 @@ int main() {
             SIMPLE_PB* spb = get_pb(fp);
             memcpy(&t, spb->target, sizeof(struct TEST));
             printf("a:%u\nb:%u\nc:%u\nd:%llu\ne:%s\n", t.a, t.b, t.c, t.d, t.e);
+            printf("Struct size: %u, read: %u\n", spb->struct_len, spb->real_len);
         } else perror("[SPB]");
     } else perror("[SPB]");
 }
\ No newline at end of file