diff --git a/test/mock_syscall.hpp b/test/mock_syscall.hpp
new file mode 100644
index 0000000..d219999
--- /dev/null
+++ b/test/mock_syscall.hpp
@@ -0,0 +1,12 @@
+#pragma once
+
+/** @brief Adds the given interface and addr info
+ *         into the ifaddr list.
+ *  @param[in] name - Interface name.
+ *  @param[in] addr - IP address.
+ *  @param[in] mask - subnet mask.
+ *  @param[in] flags - Interface flags.
+ */
+
+void mock_addIP(const char* name, const char* addr, const char* mask,
+                unsigned int flags);