diff --git a/test/internal_sys_mock.hpp b/test/internal_sys_mock.hpp
index 63c0b0c..fc98561 100644
--- a/test/internal_sys_mock.hpp
+++ b/test/internal_sys_mock.hpp
@@ -15,6 +15,7 @@
     virtual ~InternalSysMock() = default;
 
     MOCK_CONST_METHOD2(open, int(const char*, int));
+    MOCK_CONST_METHOD3(read, int(int, void*, std::size_t));
     MOCK_CONST_METHOD1(close, int(int));
     MOCK_CONST_METHOD6(mmap, void*(void*, std::size_t, int, int, int, off_t));
     MOCK_CONST_METHOD2(munmap, int(void*, std::size_t));