diff --git a/src/inet.h b/src/inet.h
new file mode 100644
index 0000000..3b0453e
--- /dev/null
+++ b/src/inet.h
@@ -0,0 +1,36 @@
+/*=========================================================================*\
+* Internet domain class
+* RCS ID: $Id$
+\*=========================================================================*/
+#ifndef INET_H_
+#define INET_H_ 
+
+#include <lua.h>
+#include "lssock.h"
+
+/* class name */
+#define INET_CLASS "luasocket(inet)"
+
+/*-------------------------------------------------------------------------*\
+* Socket fields
+\*-------------------------------------------------------------------------*/
+#define INET_FIELDS SOCK_FIELDS
+
+/*-------------------------------------------------------------------------*\
+* Socket structure
+\*-------------------------------------------------------------------------*/
+typedef t_sock t_inet;
+typedef t_inet *p_inet;
+
+/*-------------------------------------------------------------------------*\
+* Exported functions
+\*-------------------------------------------------------------------------*/
+void inet_open(lua_State *L);
+void inet_construct(lua_State *L, p_inet inet);
+void inet_inherit(lua_State *L, cchar *lsclass);
+
+cchar *inet_tryconnect(p_sock sock, cchar *address, ushort);
+cchar *inet_trybind(p_sock sock, cchar *address, ushort);
+cchar *inet_trysocket(p_inet inet, int type);
+
+#endif /* INET_H_ */
diff --git a/src/select.h b/src/select.h
new file mode 100644
index 0000000..c3267ad
--- /dev/null
+++ b/src/select.h
@@ -0,0 +1,7 @@
+#ifndef SLCT_H_
+#define SLCT_H_
+
+void select_addclass(lua_State *L, cchar *lsclass);
+void select_open(lua_State *L);
+
+#endif
diff --git a/src/socket.h b/src/socket.h
new file mode 100644
index 0000000..c9dee20
--- /dev/null
+++ b/src/socket.h
@@ -0,0 +1,18 @@
+#ifndef SOCK_H_
+#define SOCK_H_ 
+
+#include <lua.h>
+#include "lsfd.h"
+
+#define SOCK_CLASS "luasocket(sock)"
+
+#define SOCK_FIELDS FD_FIELDS
+
+typedef t_fd t_sock;
+typedef t_sock *p_sock;
+
+void sock_open(lua_State *L);
+void sock_construct(lua_State *L, p_sock sock);
+void sock_inherit(lua_State *L, cchar *lsclass);
+
+#endif /* SOCK_H_ */
diff --git a/src/timeout.c b/src/timeout.c
new file mode 100644
index 0000000..266a86e
--- /dev/null
+++ b/src/timeout.c
@@ -0,0 +1,160 @@
+/*=========================================================================*\
+* Timeout management functions
+\*=========================================================================*/
+#include <lua.h>
+#include <lauxlib.h>
+
+#include "lspriv.h"
+#include "lstm.h"
+
+#include <stdio.h>
+
+#ifdef WIN32
+#include <windows.h>
+#else
+#include <sys/times.h>
+#include <time.h>
+#include <unistd.h>
+#endif
+
+/*=========================================================================*\
+* Internal function prototypes
+\*=========================================================================*/
+#ifdef _DEBUG
+static int tm_lua_time(lua_State *L);
+static int tm_lua_sleep(lua_State *L);
+#endif
+
+/*=========================================================================*\
+* Exported functions.
+\*=========================================================================*/
+/*-------------------------------------------------------------------------*\
+* Sets timeout limits
+* Input
+*   tm: timeout control structure
+*   mode: block or return timeout
+*   value: timeout value in miliseconds
+\*-------------------------------------------------------------------------*/
+void tm_set(p_tm tm, int tm_block, int tm_return)
+{
+    tm->tm_block = tm_block;
+    tm->tm_return = tm_return;
+}
+
+/*-------------------------------------------------------------------------*\
+* Returns timeout limits
+* Input
+*   tm: timeout control structure
+*   mode: block or return timeout
+*   value: timeout value in miliseconds
+\*-------------------------------------------------------------------------*/
+void tm_get(p_tm tm, int *tm_block, int *tm_return)
+{
+    if (tm_block) *tm_block = tm->tm_block;
+    if (tm_return) *tm_return = tm->tm_return;
+}
+
+/*-------------------------------------------------------------------------*\
+* Determines how much time we have left for the current io operation
+* an IO write operation.
+* Input
+*   tm: timeout control structure
+* Returns
+*   the number of ms left or -1 if there is no time limit
+\*-------------------------------------------------------------------------*/
+int tm_getremaining(p_tm tm)
+{
+    /* no timeout */
+    if (tm->tm_block < 0 && tm->tm_return < 0)
+        return -1;
+    /* there is no block timeout, we use the return timeout */
+    else if (tm->tm_block < 0)
+        return MAX(tm->tm_return - tm_gettime() + tm->tm_start, 0);
+    /* there is no return timeout, we use the block timeout */
+    else if (tm->tm_return < 0) 
+        return tm->tm_block;
+    /* both timeouts are specified */
+    else return MIN(tm->tm_block, 
+            MAX(tm->tm_return - tm_gettime() + tm->tm_start, 0));
+}
+
+/*-------------------------------------------------------------------------*\
+* Marks the operation start time in sock structure
+* Input
+*   tm: timeout control structure
+\*-------------------------------------------------------------------------*/
+void tm_markstart(p_tm tm)
+{
+    tm->tm_start = tm_gettime();
+    tm->tm_end = tm->tm_start;
+}
+
+/*-------------------------------------------------------------------------*\
+* Returns the length of the operation in ms
+* Input
+*   tm: timeout control structure
+\*-------------------------------------------------------------------------*/
+int tm_getelapsed(p_tm tm)
+{
+    return tm->tm_end - tm->tm_start;
+}
+
+/*-------------------------------------------------------------------------*\
+* Gets time in ms, relative to system startup.
+* Returns
+*   time in ms.
+\*-------------------------------------------------------------------------*/
+#ifdef WIN32
+int tm_gettime(void) 
+{
+    return GetTickCount();
+}
+#else
+int tm_gettime(void) 
+{
+    struct tms t;
+    return (times(&t)*1000)/CLK_TCK;
+}
+#endif
+
+/*-------------------------------------------------------------------------*\
+* Initializes module
+\*-------------------------------------------------------------------------*/
+void tm_open(lua_State *L)
+{
+    (void) L;
+#ifdef _DEBUG
+    lua_pushcfunction(L, tm_lua_time);
+    lua_setglobal(L, "_time");
+    lua_pushcfunction(L, tm_lua_sleep);
+    lua_setglobal(L, "_sleep");
+#endif
+}
+
+/*=========================================================================*\
+* Test support functions
+\*=========================================================================*/
+/*-------------------------------------------------------------------------*\
+* Returns the time the system has been up, in secconds.
+\*-------------------------------------------------------------------------*/
+#ifdef _DEBUG
+static int tm_lua_time(lua_State *L)
+{
+    lua_pushnumber(L, tm_gettime()/1000.0);
+    return 1;
+}
+
+/*-------------------------------------------------------------------------*\
+* Sleep for n seconds.
+\*-------------------------------------------------------------------------*/
+int tm_lua_sleep(lua_State *L)
+{
+    double n = luaL_check_number(L, 1);
+#ifdef WIN32
+    Sleep(n*1000);
+#else
+    sleep(n);
+#endif
+    return 0;
+}
+#endif
diff --git a/src/timeout.h b/src/timeout.h
new file mode 100644
index 0000000..af7e591
--- /dev/null
+++ b/src/timeout.h
@@ -0,0 +1,20 @@
+#ifndef _TM_H
+#define _TM_H
+
+typedef struct t_tm_tag {
+    int tm_return;
+    int tm_block;
+    int tm_start;
+    int tm_end;
+} t_tm;
+typedef t_tm *p_tm;
+
+void tm_set(p_tm tm, int tm_block, int tm_return);
+int tm_getremaining(p_tm tm);
+int tm_getelapsed(p_tm tm);
+int tm_gettime(void);
+void tm_get(p_tm tm, int *tm_block, int *tm_return);
+void tm_markstart(p_tm tm);
+void tm_open(lua_State *L);
+
+#endif
diff --git a/src/udp.c b/src/udp.c
new file mode 100644
index 0000000..0dc0df8
--- /dev/null
+++ b/src/udp.c
@@ -0,0 +1,287 @@
+/*=========================================================================*\
+* UDP socket object implementation (inherits from sock and inet)
+\*=========================================================================*/
+#include <string.h>
+
+#include <lua.h>
+#include <lauxlib.h>
+
+#include "lsinet.h"
+#include "lsudp.h"
+#include "lscompat.h"
+#include "lsselect.h"
+
+/*=========================================================================*\
+* Internal function prototypes.
+\*=========================================================================*/
+static int udp_lua_send(lua_State *L);
+static int udp_lua_sendto(lua_State *L);
+static int udp_lua_receive(lua_State *L);
+static int udp_lua_receivefrom(lua_State *L);
+static int udp_lua_setpeername(lua_State *L);
+static int udp_lua_setsockname(lua_State *L);
+
+static int udp_global_udpsocket(lua_State *L);
+
+static struct luaL_reg funcs[] = {
+    {"send", udp_lua_send},
+    {"sendto", udp_lua_sendto},
+    {"receive", udp_lua_receive},
+    {"receivefrom", udp_lua_receivefrom},
+    {"setpeername", udp_lua_setpeername},
+    {"setsockname", udp_lua_setsockname},
+};
+
+/*=========================================================================*\
+* Exported functions
+\*=========================================================================*/
+/*-------------------------------------------------------------------------*\
+* Initializes module
+\*-------------------------------------------------------------------------*/
+void udp_open(lua_State *L)
+{
+    unsigned int i;
+    priv_newclass(L, UDP_CLASS);
+    udp_inherit(L, UDP_CLASS);
+    /* declare global functions */
+    lua_pushcfunction(L, udp_global_udpsocket);
+    lua_setglobal(L, "udpsocket");
+    for (i = 0; i < sizeof(funcs)/sizeof(funcs[0]); i++) 
+        priv_newglobalmethod(L, funcs[i].name);
+    /* make class selectable */
+    select_addclass(L, UDP_CLASS);
+}
+
+/*-------------------------------------------------------------------------*\
+* Hook object methods to methods table.
+\*-------------------------------------------------------------------------*/
+void udp_inherit(lua_State *L, cchar *lsclass)
+{
+    unsigned int i;
+    inet_inherit(L, lsclass);
+    for (i = 0; i < sizeof(funcs)/sizeof(funcs[0]); i++) {
+        lua_pushcfunction(L, funcs[i].func);
+        priv_setmethod(L, lsclass, funcs[i].name);
+    }
+}
+
+/*-------------------------------------------------------------------------*\
+* Initializes socket structure 
+\*-------------------------------------------------------------------------*/
+void udp_construct(lua_State *L, p_udp udp)
+{
+    inet_construct(L, (p_inet) udp);
+    udp->udp_connected = 0;
+}
+
+/*-------------------------------------------------------------------------*\
+* Creates a socket structure and initializes it. A socket object is
+* left in the Lua stack.
+* Returns
+*   pointer to allocated structure
+\*-------------------------------------------------------------------------*/
+p_udp udp_push(lua_State *L)
+{
+    p_udp udp = (p_udp) lua_newuserdata(L, sizeof(t_udp));
+    priv_setclass(L, UDP_CLASS);
+    udp_construct(L, udp);
+    return udp;
+}
+
+/*=========================================================================*\
+* Socket table constructors
+\*=========================================================================*/
+/*-------------------------------------------------------------------------*\
+* Creates a udp socket object and returns it to the Lua script. 
+* Lua Input: [options]
+*   options: socket options table
+* Lua Returns
+*   On success: udp socket
+*   On error: nil, followed by an error message
+\*-------------------------------------------------------------------------*/
+static int udp_global_udpsocket(lua_State *L)
+{
+    int oldtop = lua_gettop(L);
+    p_udp udp = udp_push(L);
+    cchar *err = inet_trysocket((p_inet) udp, SOCK_DGRAM);
+    if (err) {
+        lua_pushnil(L);
+        lua_pushstring(L, err);
+        return 2;
+    }
+    if (oldtop < 1) return 1;
+    err = compat_trysetoptions(L, udp->fd);
+    if (err) {
+        lua_pushnil(L);
+        lua_pushstring(L, err);
+        return 2;
+    }
+    return 1;
+}
+
+/*=========================================================================*\
+* Socket table methods
+\*=========================================================================*/
+/*-------------------------------------------------------------------------*\
+* Receives data from a UDP socket
+* Lua Input: sock [, wanted]
+*   sock: client socket created by the connect function
+*   wanted: the number of bytes expected (default: LUASOCKET_UDPBUFFERSIZE)
+* Lua Returns
+*   On success: datagram received
+*   On error: nil, followed by an error message
+\*-------------------------------------------------------------------------*/
+static int udp_lua_receive(lua_State *L)
+{
+    p_udp udp = (p_udp) lua_touserdata(L, 1);
+    unsigned char buffer[UDP_DATAGRAMSIZE];
+    size_t got, wanted = (size_t) luaL_opt_number(L, 2, sizeof(buffer));
+    int err;
+    p_tm tm = &udp->base_tm;
+    wanted = MIN(wanted, sizeof(buffer));
+    tm_markstart(tm);
+    err = compat_recv(udp->fd, buffer, wanted, &got, tm_getremaining(tm));
+    if (err == PRIV_CLOSED) err = PRIV_REFUSED;
+    if (err != PRIV_DONE) lua_pushnil(L);
+    else lua_pushlstring(L, buffer, got);
+    priv_pusherror(L, err);
+    return 2;
+}
+
+/*-------------------------------------------------------------------------*\
+* Receives a datagram from a UDP socket
+* Lua Input: sock [, wanted]
+*   sock: client socket created by the connect function
+*   wanted: the number of bytes expected (default: LUASOCKET_UDPBUFFERSIZE)
+* Lua Returns
+*   On success: datagram received, ip and port of sender
+*   On error: nil, followed by an error message
+\*-------------------------------------------------------------------------*/
+static int udp_lua_receivefrom(lua_State *L)
+{
+    p_udp udp = (p_udp) lua_touserdata(L, 1);
+    p_tm tm = &udp->base_tm;
+    struct sockaddr_in peer;
+    size_t peer_len = sizeof(peer);
+    unsigned char buffer[UDP_DATAGRAMSIZE];
+    size_t wanted = (size_t) luaL_opt_number(L, 2, sizeof(buffer));
+    size_t got;
+    int err;
+    if (udp->udp_connected) lua_error(L, "receivefrom on connected socket");
+    tm_markstart(tm);
+    wanted = MIN(wanted, sizeof(buffer));
+    err = compat_recvfrom(udp->fd, buffer, wanted, &got, tm_getremaining(tm),
+            (SA *) &peer, &peer_len);
+    if (err == PRIV_CLOSED) err = PRIV_REFUSED;
+    if (err == PRIV_DONE) {
+        lua_pushlstring(L, buffer, got);
+        lua_pushstring(L, inet_ntoa(peer.sin_addr));
+        lua_pushnumber(L, ntohs(peer.sin_port));
+        return 3;
+    } else {
+        lua_pushnil(L);
+        priv_pusherror(L, err);
+        return 2;
+    }
+}
+
+/*-------------------------------------------------------------------------*\
+* Send data through a connected UDP socket
+* Lua Input: sock, data
+*   sock: udp socket
+*   data: data to be sent
+* Lua Returns
+*   On success: nil, followed by the total number of bytes sent
+*   On error: error message
+\*-------------------------------------------------------------------------*/
+static int udp_lua_send(lua_State *L)
+{
+    p_udp udp = (p_udp) lua_touserdata(L, 1);
+    p_tm tm = &udp->base_tm;
+    size_t wanted, sent = 0;
+    int err;
+    cchar *data = luaL_check_lstr(L, 2, &wanted);
+    if (!udp->udp_connected) lua_error(L, "send on unconnected socket");
+    tm_markstart(tm);
+    err = compat_send(udp->fd, data, wanted, &sent, tm_getremaining(tm));
+    priv_pusherror(L, err == PRIV_CLOSED ? PRIV_REFUSED : err);
+    lua_pushnumber(L, sent);
+    return 2;
+}
+
+/*-------------------------------------------------------------------------*\
+* Send data through a unconnected UDP socket
+* Lua Input: sock, data, ip, port
+*   sock: udp socket
+*   data: data to be sent
+*   ip: ip address of target
+*   port: port in target
+* Lua Returns
+*   On success: nil, followed by the total number of bytes sent
+*   On error: error message
+\*-------------------------------------------------------------------------*/
+static int udp_lua_sendto(lua_State *L)
+{
+    p_udp udp = (p_udp) lua_touserdata(L, 1);
+    size_t wanted, sent = 0;
+    cchar *data = luaL_check_lstr(L, 2, &wanted);
+    cchar *ip = luaL_check_string(L, 3);
+    ushort port = (ushort) luaL_check_number(L, 4);
+    p_tm tm = &udp->base_tm;
+    struct sockaddr_in peer;
+    int err;
+    if (udp->udp_connected) lua_error(L, "sendto on connected socket");
+    memset(&peer, 0, sizeof(peer));
+    if (!inet_aton(ip, &peer.sin_addr)) lua_error(L, "invalid ip address");
+    peer.sin_family = AF_INET;
+    peer.sin_port = htons(port);
+    tm_markstart(tm);
+    err = compat_sendto(udp->fd, data, wanted, &sent, tm_getremaining(tm),
+            (SA *) &peer, sizeof(peer));
+    priv_pusherror(L, err == PRIV_CLOSED ? PRIV_REFUSED : err);
+    lua_pushnumber(L, sent);
+    return 2;
+}
+
+/*-------------------------------------------------------------------------*\
+* Associates a local address to an UDP socket
+* Lua Input: address, port
+*   address: host name or ip address to bind to 
+*   port: port to bind to
+* Lua Returns
+*   On success: nil
+*   On error: error message
+\*-------------------------------------------------------------------------*/
+static int udp_lua_setsockname(lua_State * L)
+{
+    p_udp udp = (p_udp) lua_touserdata(L, 1);
+    cchar *address = luaL_check_string(L, 2);
+    ushort port = (ushort) luaL_check_number(L, 3);
+    cchar *err = inet_trybind((p_inet) udp, address, port);
+    if (err) lua_pushstring(L, err);
+    else lua_pushnil(L);
+    return 1;
+}
+
+/*-------------------------------------------------------------------------*\
+* Sets a peer for a UDP socket
+* Lua Input: address, port
+*   address: remote host name
+*   port: remote host port
+* Lua Returns
+*   On success: nil
+*   On error: error message
+\*-------------------------------------------------------------------------*/
+static int udp_lua_setpeername(lua_State *L)
+{
+    p_udp udp = (p_udp) lua_touserdata(L, 1);
+    cchar *address = luaL_check_string(L, 2);
+    ushort port = (ushort) luaL_check_number(L, 3);
+    cchar *err = inet_tryconnect((p_inet) udp, address, port);
+    if (!err) {
+        udp->udp_connected = 1;
+        lua_pushnil(L);
+    } else lua_pushstring(L, err);
+    return 1;
+}
+
diff --git a/src/udp.h b/src/udp.h
new file mode 100644
index 0000000..3c82c29
--- /dev/null
+++ b/src/udp.h
@@ -0,0 +1,24 @@
+#ifndef UDP_H_ 
+#define UDP_H_
+
+#include "lsinet.h"
+
+#define UDP_CLASS "luasocket(UDP socket)"
+
+#define UDP_DATAGRAMSIZE 576
+
+#define UDP_FIELDS \
+    INET_FIELDS; \
+    int udp_connected
+
+typedef struct t_udp_tag {
+    UDP_FIELDS; 
+} t_udp;
+typedef t_udp *p_udp;
+
+void udp_inherit(lua_State *L, cchar *lsclass);
+void udp_construct(lua_State *L, p_udp udp);
+void udp_open(lua_State *L);
+p_udp udp_push(lua_State *L);
+
+#endif