diff --git a/version3.0/lib.nas b/version3.0/lib.nas
new file mode 100644
index 0000000..c0d63d9
--- /dev/null
+++ b/version3.0/lib.nas
@@ -0,0 +1,41 @@
+var print=func(elements...)
+{
+    nasal_call_builtin_std_cout(elements);
+    return nil;
+};
+var append=func(vector,elements...)
+{
+    nasal_call_builtin_push_back(vector,elements);
+    return nil;
+}
+var setsize=func(vector,size)
+{
+    nasal_call_builtin_set_size(vector,size);
+    return nil;
+}
+var system=func(str)
+{
+    nasal_call_builtin_system(str);
+    return;
+}
+var input=func()
+{
+    return nasal_call_builtin_input();
+}
+var sleep=func(duration)
+{
+    nasal_call_builtin_sleep(duration);
+    return;
+}
+var io=
+{
+    fin:func(filename)
+    {
+        return nasal_call_builtin_finput(filename);
+    },
+    fout:func(filename,str)
+    {
+        nasal_call_builtin_foutput(filename,str);
+        return;
+    }
+};
\ No newline at end of file
diff --git a/version3.0/nasal_builtin.h b/version3.0/nasal_builtin.h
index 9011425..a7e55c4 100644
--- a/version3.0/nasal_builtin.h
+++ b/version3.0/nasal_builtin.h
@@ -198,4 +198,64 @@ int nasal_runtime::builtin_sleep(int local_scope_addr)
     return ret_addr;
 }
 
+int nasal_runtime::builtin_finput(int local_scope_addr)
+{
+    int value_addr=-1;
+    if(local_scope_addr>=0)
+        value_addr=nasal_vm.gc_get(local_scope_addr).get_closure().get_value_address("filename");
+    if(value_addr<0 || nasal_vm.gc_get(value_addr).get_type()!=vm_string)
+    {
+        std::cout<<">> [runtime] builtin_finput: cannot find values or wrong value type(must be string)."<<std::endl;
+        ++error;
+        return -1;
+    }
+    std::string filename=nasal_vm.gc_get(value_addr).get_string();
+    std::ifstream fin(filename);
+    std::string file_content="";
+    if(!fin.fail())
+        while(!fin.eof())
+        {
+            file_content.push_back(fin.get());
+            if(fin.eof())
+                break;
+        }
+    else
+        file_content="cannot open file named \'"+filename+"\'.";
+    fin.close();
+    int ret_addr=nasal_vm.gc_alloc();
+    nasal_vm.gc_get(ret_addr).set_type(vm_string);
+    nasal_vm.gc_get(ret_addr).set_string(file_content);
+    return ret_addr;
+}
+
+int nasal_runtime::builtin_foutput(int local_scope_addr)
+{
+    int value_addr=-1;
+    if(local_scope_addr>=0)
+        value_addr=nasal_vm.gc_get(local_scope_addr).get_closure().get_value_address("filename");
+    if(value_addr<0 || nasal_vm.gc_get(value_addr).get_type()!=vm_string)
+    {
+        std::cout<<">> [runtime] builtin_foutput: cannot find values or wrong value type(filename must be string)."<<std::endl;
+        ++error;
+        return -1;
+    }
+    int str_value_addr=-1;
+    if(local_scope_addr>=0)
+        str_value_addr=nasal_vm.gc_get(local_scope_addr).get_closure().get_value_address("str");
+    if(str_value_addr<0 || nasal_vm.gc_get(str_value_addr).get_type()!=vm_string)
+    {
+        std::cout<<">> [runtime] builtin_foutput: cannot find values or wrong value type(file's content must be string)."<<std::endl;
+        ++error;
+        return -1;
+    }
+    std::string filename=nasal_vm.gc_get(value_addr).get_string();
+    std::string file_content=nasal_vm.gc_get(str_value_addr).get_string();
+    std::ofstream fout(filename);
+    fout<<file_content;
+    fout.close();
+    int ret_addr=nasal_vm.gc_alloc();
+    nasal_vm.gc_get(ret_addr).set_type(vm_nil);
+    return ret_addr;
+}
+
 #endif
\ No newline at end of file
diff --git a/version3.0/nasal_runtime.h b/version3.0/nasal_runtime.h
index fa4894d..dc446e0 100644
--- a/version3.0/nasal_runtime.h
+++ b/version3.0/nasal_runtime.h
@@ -10,7 +10,7 @@ enum runtime_returned_state
     rt_exit_without_error
 };
 
-#define BUILTIN_FUNC_NUM 6
+#define BUILTIN_FUNC_NUM 8
 std::string builtin_func_name[BUILTIN_FUNC_NUM]=
 {
     "nasal_call_builtin_std_cout",
@@ -18,7 +18,9 @@ std::string builtin_func_name[BUILTIN_FUNC_NUM]=
     "nasal_call_builtin_set_size",
     "nasal_call_builtin_system",
     "nasal_call_builtin_input",
-    "nasal_call_builtin_sleep"
+    "nasal_call_builtin_sleep",
+    "nasal_call_builtin_finput",
+    "nasal_call_builtin_foutput"
 };
 
 class nasal_runtime
@@ -83,6 +85,8 @@ private:
     int builtin_system(int);
     int builtin_input(int);
     int builtin_sleep(int);
+    int builtin_finput(int);
+    int builtin_foutput(int);
 public:
     nasal_runtime();
     ~nasal_runtime();
@@ -1073,6 +1077,8 @@ int nasal_runtime::call_builtin_function(nasal_ast& node,int local_scope_addr)
         case 3:ret_value_addr=builtin_system(local_scope_addr);break;
         case 4:ret_value_addr=builtin_input(local_scope_addr);break;
         case 5:ret_value_addr=builtin_sleep(local_scope_addr);break;
+        case 6:ret_value_addr=builtin_finput(local_scope_addr);break;
+        case 7:ret_value_addr=builtin_foutput(local_scope_addr);break;
     }
     return ret_value_addr;
 }