Added DLL_EXPORT declaration for tstrerror(), taosGetErrno(), taos_data_type()

src/inc/taos.h

@@ -110,7 +110,7 @@ DLL_EXPORT TAOS *taos_connect(const char *ip, const char *user, const char *pass
 DLL_EXPORT TAOS *taos_connect_auth(const char *ip, const char *user, const char *auth, const char *db, uint16_t port);
 DLL_EXPORT void  taos_close(TAOS *taos);
 
-const char *taos_data_type(int type);
+DLL_EXPORT const char *taos_data_type(int type);
 
 typedef struct TAOS_BIND {
   int            buffer_type;

src/inc/taoserror.h

@@ -29,9 +29,9 @@ extern "C" {
 #define TAOS_SUCCEEDED(err)                 ((err) >= 0)
 #define TAOS_FAILED(err)                    ((err) < 0)
 
-const char* tstrerror(int32_t err);
+DLL_EXPORT const char* tstrerror(int32_t err);
 
-int32_t* taosGetErrno();
+DLL_EXPORT int32_t* taosGetErrno();
 #define terrno                              (*taosGetErrno())
 
 #define TSDB_CODE_SUCCESS                   0