use same parameter name as in the prototype
diff --git a/tommath.h b/tommath.h
index 1e0192b..a8ad230 100644
--- a/tommath.h
+++ b/tommath.h
@@ -385,8 +385,8 @@ mp_err mp_unpack(mp_int *rop, size_t count, mp_order order, size_t size, mp_endi
/* pack binary data */
size_t mp_pack_count(const mp_int *a, size_t nails, size_t size) MP_WUR;
-mp_err mp_pack(void *rop, size_t maxcount, size_t *writtencount, mp_order order, size_t size, mp_endian endian,
- size_t nails, const mp_int *op) MP_WUR;
+mp_err mp_pack(void *rop, size_t maxcount, size_t *written, mp_order order, size_t size,
+ mp_endian endian, size_t nails, const mp_int *op) MP_WUR;
/* ---> digit manipulation <--- */