msvcrt: Implement ecvt_s.
diff --git a/dlls/msvcr90/msvcr90.spec b/dlls/msvcr90/msvcr90.spec
index feaf80e..5baee98 100644
--- a/dlls/msvcr90/msvcr90.spec
+++ b/dlls/msvcr90/msvcr90.spec
@@ -415,7 +415,7 @@
@ cdecl _dup2(long long) msvcrt._dup2
@ cdecl _dupenv_s(ptr ptr str) msvcrt._dupenv_s
@ cdecl _ecvt(double long ptr ptr) msvcrt._ecvt
-@ stub _ecvt_s
+@ cdecl _ecvt_s(str long double long ptr ptr) msvcrt._ecvt_s
@ cdecl _encode_pointer(ptr) MSVCR90_encode_pointer
@ cdecl _encoded_null()
@ cdecl _endthread() msvcrt._endthread