diff --git a/src/l52util.c b/src/l52util.c
index 70dc7b9..af64402 100644
--- a/src/l52util.c
+++ b/src/l52util.c
@@ -155,3 +155,27 @@ void *lutil_newudatap_impl(lua_State *L, size_t size, const void *p){
   lutil_setmetatablep(L, p);
   return obj;
 }
+
+void lutil_pushint64(lua_State *L, int64_t v){
+  if(sizeof(lua_Integer) >= sizeof(int64_t)){
+    lua_pushinteger(L, (lua_Integer)v);
+    return;
+  }
+  lua_pushnumber(L, (lua_Number)v);
+}
+
+int64_t lutil_checkint64(lua_State *L, int idx){
+  if(sizeof(lua_Integer) >= sizeof(int64_t))
+    return luaL_checkinteger(L, idx);
+  return (int64_t)luaL_checknumber(L, idx);
+}
+
+int64_t lutil_optint64(lua_State *L, int idx, int64_t v){
+  if(sizeof(lua_Integer) >= sizeof(int64_t))
+    return luaL_optinteger(L, idx, v);
+  return (int64_t)luaL_optnumber(L, idx, v);
+}
+
+void lutil_pushnvalues(lua_State *L, int n){
+  for(;n;--n) lua_pushvalue(L, -n);
+}
diff --git a/src/l52util.h b/src/l52util.h
index 560fe10..84bc8ce 100644
--- a/src/l52util.h
+++ b/src/l52util.h
@@ -13,47 +13,52 @@
 
 #include "lua.h"
 #include "lauxlib.h"
+#include <stdint.h>
 
 #if LUA_VERSION_NUM >= 503 /* Lua 5.3 */
 
-#ifndef luaL_optint
-# define luaL_optint luaL_optinteger
-#endif
-
 #ifndef luaL_checkint
-# define luaL_checkint luaL_checkinteger
+#define luaL_checkint  luaL_checkinteger
 #endif
 
 #ifndef luaL_checklong
-# define luaL_checklong luaL_checkinteger
+#define luaL_checklong  luaL_checkinteger
+#endif
+
+#ifndef luaL_optint
+#define luaL_optint luaL_optinteger
+#endif
+
+#ifndef luaL_optlong
+#define luaL_optlong luaL_optinteger
 #endif
 
 #endif
 
+#if LUA_VERSION_NUM >= 502 /* Lua 5.2 */
 
-#if LUA_VERSION_NUM >= 502 // lua 5.2
+/* lua_rawgetp */
+/* lua_rawsetp */
+/* luaL_setfuncs */
+/* lua_absindex */
 
-// lua_rawgetp
-// lua_rawsetp
-// luaL_setfuncs
-// lua_absindex
 #ifndef lua_objlen
-
 #define lua_objlen      lua_rawlen
-
 #endif
 
 int   luaL_typerror (lua_State *L, int narg, const char *tname);
 
 #ifndef luaL_register
-
 void luaL_register (lua_State *L, const char *libname, const luaL_Reg *l);
-
 #endif
 
-#else                      // lua 5.1
+#ifndef lua_equal
+#define lua_equal(L,idx1,idx2) lua_compare(L,(idx1),(idx2),LUA_OPEQ)
+#endif
 
-// functions form lua 5.2
+#else                      /* Lua 5.1 */
+
+/* functions form lua 5.2 */
 
 # define lua_absindex(L, i) (((i)>0)?(i):((i)<=LUA_REGISTRYINDEX?(i):(lua_gettop(L)+(i)+1)))
 # define lua_rawlen  lua_objlen
@@ -78,5 +83,12 @@ int   lutil_createmetap   (lua_State *L, const void *p, const luaL_Reg *methods,
 
 void *lutil_newudatap_impl     (lua_State *L, size_t size, const void *p);
 
-#endif
+void lutil_pushint64(lua_State *L, int64_t v);
 
+int64_t lutil_checkint64(lua_State *L, int idx);
+
+int64_t lutil_optint64(lua_State *L, int idx, int64_t v);
+
+void lutil_pushnvalues(lua_State *L, int n);
+
+#endif
diff --git a/src/lcmulti.c b/src/lcmulti.c
index c2c017c..34f5b81 100644
--- a/src/lcmulti.c
+++ b/src/lcmulti.c
@@ -226,6 +226,18 @@ static int lcurl_multi_timeout(lua_State *L){
   return 1;
 }
 
+static int lcurl_multi_socket_action(lua_State *L){
+  lcurl_multi_t *p = lcurl_getmulti(L);
+  curl_socket_t s  = lutil_checkint64(L, 2);
+  int n, mask      = lutil_checkint64(L, 3);
+  CURLMcode code   = curl_multi_socket_action(p->curl, s, mask, &n);
+  if(code != CURLM_OK){
+    lcurl_fail_ex(L, p->err_mode, LCURL_ERROR_MULTI, code);
+  }
+  lua_pushinteger(L, n);
+  return 1;
+}
+
 //{ OPTIONS
 static int lcurl_opt_set_long_(lua_State *L, int opt){
   lcurl_multi_t *p = lcurl_getmulti(L);
@@ -313,7 +325,7 @@ static int lcurl_multi_set_callback(lua_State *L,
   return 1;
 }
 
-//{Timer
+//{ Timer
 
 int lcurl_multi_timer_callback(CURLM *multi, long ms, void *arg){
   lcurl_multi_t *p = arg;
@@ -347,7 +359,6 @@ int lcurl_multi_timer_callback(CURLM *multi, long ms, void *arg){
   return ret;
 }
 
-
 static int lcurl_multi_set_TIMERFUNCTION(lua_State *L){
   lcurl_multi_t *p = lcurl_getmulti(L);
   return lcurl_multi_set_callback(L, p, &p->tm,
@@ -358,6 +369,43 @@ static int lcurl_multi_set_TIMERFUNCTION(lua_State *L){
 
 //}
 
+//{ Socket
+
+static int lcurl_multi_socket_callback(CURL *easy, curl_socket_t s, int what, void *arg, void *socketp){
+  lcurl_multi_t *p = arg;
+  lua_State *L = p->L;
+  lcurl_easy_t *e;
+  int n, top = lua_gettop(L);
+
+  n = lcurl_util_push_cb(L, &p->sc);
+
+  lua_rawgeti(L, LCURL_LUA_REGISTRY, p->h_ref);
+  lua_rawgetp(L, -1, easy);
+  e = lcurl_geteasy_at(L, -1);
+  lua_remove(L, -2);
+  lutil_pushint64(L, s);
+  lua_pushinteger(L, what);
+
+  if(lua_pcall(L, n+2, 0, 0)){
+    assert(lua_gettop(L) >= top);
+    lua_settop(L, top);
+    return -1; //! @todo break perform
+  }
+
+  lua_settop(L, top);
+  return 0;
+}
+
+static int lcurl_multi_set_SOCKETFUNCTION(lua_State *L){
+  lcurl_multi_t *p = lcurl_getmulti(L);
+  return lcurl_multi_set_callback(L, p, &p->sc,
+    CURLMOPT_SOCKETFUNCTION, CURLMOPT_SOCKETDATA,
+    "socket", lcurl_multi_socket_callback
+  );
+}
+
+//}
+
 //}
 
 static int lcurl_multi_setopt(lua_State *L){
@@ -396,10 +444,12 @@ static const struct luaL_Reg lcurl_multi_methods[] = {
   {"setopt",           lcurl_multi_setopt           },
   {"wait",             lcurl_multi_wait             },
   {"timeout",          lcurl_multi_timeout          },
+  {"socket_action",    lcurl_multi_socket_action    },
 
 #define OPT_ENTRY(L, N, T, S) { "setopt_"#L, lcurl_multi_set_##N },
   #include "lcoptmulti.h"
-  OPT_ENTRY(timerfunction, TIMERFUNCTION, TTT, 0)
+  OPT_ENTRY(timerfunction,  TIMERFUNCTION,  TTT, 0)
+  OPT_ENTRY(socketfunction, SOCKETFUNCTION, TTT, 0)
 #undef OPT_ENTRY
 
   {"close",            lcurl_multi_cleanup          },
@@ -411,7 +461,8 @@ static const struct luaL_Reg lcurl_multi_methods[] = {
 static const lcurl_const_t lcurl_multi_opt[] = {
 #define OPT_ENTRY(L, N, T, S) { "OPT_MULTI_"#N, CURLMOPT_##N },
   #include "lcoptmulti.h"
-  OPT_ENTRY(timerfunction, TIMERFUNCTION, TTT, 0)
+  OPT_ENTRY(timerfunction,  TIMERFUNCTION,  TTT, 0)
+  OPT_ENTRY(socketfunction, SOCKETFUNCTION, TTT, 0)
 #undef OPT_ENTRY
 
   {NULL, 0}
diff --git a/src/lcmulti.h b/src/lcmulti.h
index 3e866de..73d767f 100644
--- a/src/lcmulti.h
+++ b/src/lcmulti.h
@@ -20,6 +20,7 @@ typedef struct lcurl_multi_tag{
   int err_mode;
   int h_ref;
   lcurl_callback_t tm;
+  lcurl_callback_t sc;
 }lcurl_multi_t;
 
 int lcurl_multi_create(lua_State *L, int error_mode);
diff --git a/src/lcopteasy.h b/src/lcopteasy.h
index 1d77f52..4da9095 100644
--- a/src/lcopteasy.h
+++ b/src/lcopteasy.h
@@ -264,6 +264,17 @@ FLG_ENTRY( HTTP_VERSION_2_0   )
 FLG_ENTRY( READFUNC_PAUSE     ) /*7.18.0*/
 FLG_ENTRY( WRITEFUNC_PAUSE    ) /*7.18.0*/
 
+FLG_ENTRY( POLL_IN            ) /*7.14.0*/
+FLG_ENTRY( POLL_INOUT         ) /*7.14.0*/
+FLG_ENTRY( POLL_NONE          ) /*7.14.0*/
+FLG_ENTRY( POLL_OUT           ) /*7.14.0*/
+FLG_ENTRY( POLL_REMOVE        ) /*7.14.0*/
+FLG_ENTRY( SOCKET_TIMEOUT     ) /*7.14.0*/
+
+FLG_ENTRY( CSELECT_ERR        ) /*7.16.3*/
+FLG_ENTRY( CSELECT_IN         ) /*7.16.3*/
+FLG_ENTRY( CSELECT_OUT        ) /*7.16.3*/
+
 #ifdef OPT_ENTRY_IS_NULL
 #  undef OPT_ENTRY
 #endif
@@ -271,3 +282,4 @@ FLG_ENTRY( WRITEFUNC_PAUSE    ) /*7.18.0*/
 #ifdef FLG_ENTRY_IS_NULL
 #  undef FLG_ENTRY
 #endif
+