/* -------------------------------------------------------------------------
- * Project: GSocket (Generic Socket) for WX
+ * Project: GSocket (Generic Socket)
* Name: gsocket.c
+ * Author: Guillermo Rodriguez Garcia <guille@iies.es>
* Purpose: GSocket main MSW file
* CVSID: $Id$
* -------------------------------------------------------------------------
*/
+/*
+ * PLEASE don't put C++ comments here - this is a C source file.
+ */
+
#ifndef __GSOCKET_STANDALONE__
#include "wx/setup.h"
#endif
#if wxUSE_SOCKETS || defined(__GSOCKET_STANDALONE__)
-
#ifndef __GSOCKET_STANDALONE__
#include "wx/msw/gsockmsw.h"
#include <ctype.h>
#include <winsock.h>
+/* if we use configure for MSW SOCKLEN_T will be already defined */
+#ifndef SOCKLEN_T
#define SOCKLEN_T int
+#endif
+
#define CLASSNAME "_GSocket_Internal_Window_Class"
#define WINDOWNAME "_GSocket_Internal_Window_Name"
WSACleanup();
}
-/* Constructors / Destructors */
+/* Constructors / Destructors for GSocket */
GSocket *GSocket_new()
{
{
socket->m_cbacks[i] = NULL;
}
- socket->m_local = NULL;
- socket->m_peer = NULL;
+ socket->m_local = NULL;
+ socket->m_peer = NULL;
socket->m_error = GSOCK_NOERROR;
- socket->m_server = FALSE;
+ socket->m_server = FALSE;
socket->m_stream = TRUE;
socket->m_non_blocking = FALSE;
socket->m_timeout.tv_sec = 10 * 60; /* 10 minutes */
if (socket->m_peer)
GAddress_destroy(socket->m_peer);
- /* Destroy socket itself */
+ /* Destroy the socket itself */
free(socket);
}
+/* GSocket_Shutdown:
+ * Disallow further read/write operations on this socket, close
+ * the fd and disable all callbacks.
+ */
void GSocket_Shutdown(GSocket *socket)
{
int evt;
/* Address handling */
+/* GSocket_SetLocal:
+ * GSocket_GetLocal:
+ * GSocket_SetPeer:
+ * GSocket_GetPeer:
+ * Set or get the local or peer address for this socket. The 'set'
+ * functions return GSOCK_NOERROR on success, an error code otherwise.
+ * The 'get' functions return a pointer to a GAddress object on success,
+ * or NULL otherwise, in which case they set the error code of the
+ * corresponding GSocket.
+ *
+ * Error codes:
+ * GSOCK_INVSOCK - the socket is not valid.
+ * GSOCK_INVADDR - the address is not valid.
+ */
GSocketError GSocket_SetLocal(GSocket *socket, GAddress *address)
{
assert(socket != NULL);
+ /* the socket must be initialized, or it must be a server */
if (socket->m_fd != INVALID_SOCKET && !socket->m_server)
{
socket->m_error = GSOCK_INVSOCK;
return GSOCK_INVSOCK;
}
+ /* check address */
if (address == NULL || address->m_family == GSOCK_NOFAMILY)
{
socket->m_error = GSOCK_INVADDR;
{
assert(socket != NULL);
+ /* check address */
if (address == NULL || address->m_family == GSOCK_NOFAMILY)
{
socket->m_error = GSOCK_INVADDR;
assert(socket != NULL);
+ /* try to get it from the m_local var first */
if (socket->m_local)
return GAddress_copy(socket->m_local);
+ /* else, if the socket is initialized, try getsockname */
if (socket->m_fd == INVALID_SOCKET)
{
socket->m_error = GSOCK_INVSOCK;
return NULL;
}
- size = sizeof(addr);
-
if (getsockname(socket->m_fd, &addr, &size) == SOCKET_ERROR)
{
socket->m_error = GSOCK_IOERR;
return NULL;
}
- address = GAddress_new();
- if (address == NULL)
+ /* got a valid address from getsockname, create a GAddress object */
+ if ((address = GAddress_new()) == NULL)
{
socket->m_error = GSOCK_MEMERR;
return NULL;
}
- err = _GAddress_translate_from(address, &addr, size);
- if (err != GSOCK_NOERROR)
+
+ if ((err = _GAddress_translate_from(address, &addr, size)) != GSOCK_NOERROR)
{
GAddress_destroy(address);
socket->m_error = err;
{
assert(socket != NULL);
+ /* try to get it from the m_peer var */
if (socket->m_peer)
return GAddress_copy(socket->m_peer);
/* Server specific parts */
/* GSocket_SetServer:
- * Sets up the socket as a server. It uses the "Local" field of GSocket.
- * "Local" must be set by GSocket_SetLocal() before GSocket_SetServer()
- * is called. Possible error codes are: GSOCK_INVSOCK if socket has not
- * been initialized, GSOCK_INVADDR if the local address has not been
- * defined and GSOCK_IOERR for other internal errors.
+ * Sets up this socket as a server. The local address must have been
+ * set with GSocket_SetLocal() before GSocket_SetServer() is called.
+ * Returns GSOCK_NOERROR on success, one of the following otherwise:
+ *
+ * Error codes:
+ * GSOCK_INVSOCK - the socket is in use.
+ * GSOCK_INVADDR - the local address has not been set.
+ * GSOCK_IOERR - low-level error.
*/
GSocketError GSocket_SetServer(GSocket *sck)
{
assert(sck != NULL);
+ /* must not be in use */
if (sck->m_fd != INVALID_SOCKET)
{
sck->m_error = GSOCK_INVSOCK;
return GSOCK_INVSOCK;
}
+ /* the local addr must have been set */
if (!sck->m_local)
{
sck->m_error = GSOCK_INVADDR;
ioctlsocket(sck->m_fd, FIONBIO, (u_long FAR *) &arg);
_GSocket_Enable_Events(sck);
- /* Bind the socket to the LOCAL address */
- if (bind(sck->m_fd, sck->m_local->m_addr, sck->m_local->m_len) != 0)
- {
- closesocket(sck->m_fd);
- sck->m_fd = INVALID_SOCKET;
- sck->m_error = GSOCK_IOERR;
- return GSOCK_IOERR;
- }
-
- /* Enable listening up to 5 connections */
- if (listen(sck->m_fd, 5) != 0)
+ /* Bind to the local address,
+ * retrieve the actual address bound,
+ * and listen up to 5 connections.
+ */
+ if ((bind(sck->m_fd, sck->m_local->m_addr, sck->m_local->m_len) != 0) ||
+ (getsockname(sck->m_fd,
+ sck->m_local->m_addr,
+ &sck->m_local->m_len) != 0) ||
+ (listen(sck->m_fd, 5) != 0))
{
closesocket(sck->m_fd);
sck->m_fd = INVALID_SOCKET;
}
/* GSocket_WaitConnection:
- * Waits for an incoming client connection.
+ * Waits for an incoming client connection. Returns a pointer to
+ * a GSocket object, or NULL if there was an error, in which case
+ * the last error field will be updated for the calling GSocket.
+ *
+ * Error codes (set in the calling GSocket)
+ * GSOCK_INVSOCK - the socket is not valid or not a server.
+ * GSOCK_TIMEDOUT - timeout, no incoming connections.
+ * GSOCK_WOULDBLOCK - the call would block and the socket is nonblocking.
+ * GSOCK_MEMERR - couldn't allocate memory.
+ * GSOCK_IOERR - low-level error.
*/
GSocket *GSocket_WaitConnection(GSocket *sck)
{
assert(sck != NULL);
+ /* Reenable CONNECTION events */
sck->m_detected &= ~GSOCK_CONNECTION_FLAG;
+ /* If the socket has already been created, we exit immediately */
if (sck->m_fd == INVALID_SOCKET || !sck->m_server)
{
sck->m_error = GSOCK_INVSOCK;
return connection;
}
-/* Non oriented connections */
-
-GSocketError GSocket_SetNonOriented(GSocket *sck)
-{
- u_long arg = 1;
-
- assert(sck != NULL);
-
- if (sck->m_fd != INVALID_SOCKET)
- {
- sck->m_error = GSOCK_INVSOCK;
- return GSOCK_INVSOCK;
- }
-
- if (!sck->m_local)
- {
- sck->m_error = GSOCK_INVADDR;
- return GSOCK_INVADDR;
- }
-
- /* Initialize all fields */
- sck->m_stream = FALSE;
- sck->m_server = FALSE;
- sck->m_oriented = FALSE;
-
- /* Create the socket */
- sck->m_fd = socket(sck->m_local->m_realfamily, SOCK_DGRAM, 0);
-
- if (sck->m_fd == INVALID_SOCKET)
- {
- sck->m_error = GSOCK_IOERR;
- return GSOCK_IOERR;
- }
-
- ioctlsocket(sck->m_fd, FIONBIO, (u_long FAR *) &arg);
- _GSocket_Enable_Events(sck);
-
- /* Bind it to the LOCAL address */
- if (bind(sck->m_fd, sck->m_local->m_addr, sck->m_local->m_len) != 0)
- {
- closesocket(sck->m_fd);
- sck->m_fd = INVALID_SOCKET;
- sck->m_error = GSOCK_IOERR;
- return GSOCK_IOERR;
- }
-
- return GSOCK_NOERROR;
-}
-
-GSocketError GSocket_SetBroadcast(GSocket *sck)
-{
- BOOL b = TRUE;
-
- assert(sck != NULL);
-
- if (GSocket_SetNonOriented(sck) != GSOCK_NOERROR)
- return sck->m_error;
-
- setsockopt(sck->m_fd, SOL_SOCKET, SO_BROADCAST,
- (const char FAR *) &b, sizeof(b));
-
- return GSOCK_NOERROR;
-}
-
/* Client specific parts */
/* GSocket_Connect:
- * Establishes a client connection to a server using the "Peer"
- * field of GSocket. "Peer" must be set by GSocket_SetPeer() before
- * GSocket_Connect() is called. Possible error codes are GSOCK_INVSOCK,
- * GSOCK_INVADDR, GSOCK_TIMEDOUT, GSOCK_WOULDBLOCK and GSOCK_IOERR.
- * If a socket is nonblocking and Connect() returns GSOCK_WOULDBLOCK,
- * the connection request can be completed later. Use GSocket_Select()
- * to check or wait for a GSOCK_CONNECTION event.
+ * For stream (connection oriented) sockets, GSocket_Connect() tries
+ * to establish a client connection to a server using the peer address
+ * as established with GSocket_SetPeer(). Returns GSOCK_NOERROR if the
+ * connection has been succesfully established, or one of the error
+ * codes listed below. Note that for nonblocking sockets, a return
+ * value of GSOCK_WOULDBLOCK doesn't mean a failure. The connection
+ * request can be completed later; you should use GSocket_Select()
+ * to poll for GSOCK_CONNECTION | GSOCK_LOST, or wait for the
+ * corresponding asynchronous events.
+ *
+ * For datagram (non connection oriented) sockets, GSocket_Connect()
+ * just sets the peer address established with GSocket_SetPeer() as
+ * default destination.
+ *
+ * Error codes:
+ * GSOCK_INVSOCK - the socket is in use or not valid.
+ * GSOCK_INVADDR - the peer address has not been established.
+ * GSOCK_TIMEDOUT - timeout, the connection failed.
+ * GSOCK_WOULDBLOCK - connection in progress (nonblocking sockets only)
+ * GSOCK_MEMERR - couldn't allocate memory.
+ * GSOCK_IOERR - low-level error.
*/
GSocketError GSocket_Connect(GSocket *sck, GSocketStream stream)
{
+ int ret, err;
u_long arg = 1;
- int type, ret, err;
assert(sck != NULL);
+ /* Enable CONNECTION events (needed for nonblocking connections) */
sck->m_detected &= ~GSOCK_CONNECTION_FLAG;
if (sck->m_fd != INVALID_SOCKET)
return GSOCK_INVADDR;
}
- /* Test whether we want the socket to be a stream (e.g. TCP) */
+ /* Streamed or dgram socket? */
sck->m_stream = (stream == GSOCK_STREAMED);
sck->m_oriented = TRUE;
sck->m_server = FALSE;
- if (sck->m_stream)
- type = SOCK_STREAM;
- else
- type = SOCK_DGRAM;
-
/* Create the socket */
- sck->m_fd = socket(sck->m_peer->m_realfamily, type, 0);
+ sck->m_fd = socket(sck->m_peer->m_realfamily,
+ sck->m_stream? SOCK_STREAM : SOCK_DGRAM, 0);
if (sck->m_fd == INVALID_SOCKET)
{
ioctlsocket(sck->m_fd, FIONBIO, (u_long FAR *) &arg);
_GSocket_Enable_Events(sck);
- /* Connect it to the PEER address, with a timeout (see below) */
+ /* Connect it to the peer address, with a timeout (see below) */
ret = connect(sck->m_fd, sck->m_peer->m_addr, sck->m_peer->m_len);
if (ret == SOCKET_ERROR)
*/
if ((err == WSAEWOULDBLOCK) && (!sck->m_non_blocking))
{
- if (_GSocket_Output_Timeout(sck) == GSOCK_TIMEDOUT)
+ err = _GSocket_Connect_Timeout(sck);
+
+ if (err != GSOCK_NOERROR)
{
closesocket(sck->m_fd);
sck->m_fd = INVALID_SOCKET;
- /* sck->m_error is set in _GSocket_Output_Timeout */
- return GSOCK_TIMEDOUT;
+ /* sck->m_error is set in _GSocket_Connect_Timeout */
}
- else
- return GSOCK_NOERROR;
+
+ return err;
}
/* If connect failed with EWOULDBLOCK and the GSocket object
}
/* If connect failed with an error other than EWOULDBLOCK,
- * then the call to GSocket_Connect has failed.
+ * then the call to GSocket_Connect() has failed.
*/
closesocket(sck->m_fd);
sck->m_fd = INVALID_SOCKET;
return GSOCK_NOERROR;
}
+/* Datagram sockets */
+
+/* GSocket_SetNonOriented:
+ * Sets up this socket as a non-connection oriented (datagram) socket.
+ * Before using this function, the local address must have been set
+ * with GSocket_SetLocal(), or the call will fail. Returns GSOCK_NOERROR
+ * on success, or one of the following otherwise.
+ *
+ * Error codes:
+ * GSOCK_INVSOCK - the socket is in use.
+ * GSOCK_INVADDR - the local address has not been set.
+ * GSOCK_IOERR - low-level error.
+ */
+GSocketError GSocket_SetNonOriented(GSocket *sck)
+{
+ u_long arg = 1;
+
+ assert(sck != NULL);
+
+ if (sck->m_fd != INVALID_SOCKET)
+ {
+ sck->m_error = GSOCK_INVSOCK;
+ return GSOCK_INVSOCK;
+ }
+
+ if (!sck->m_local)
+ {
+ sck->m_error = GSOCK_INVADDR;
+ return GSOCK_INVADDR;
+ }
+
+ /* Initialize all fields */
+ sck->m_stream = FALSE;
+ sck->m_server = FALSE;
+ sck->m_oriented = FALSE;
+
+ /* Create the socket */
+ sck->m_fd = socket(sck->m_local->m_realfamily, SOCK_DGRAM, 0);
+
+ if (sck->m_fd == INVALID_SOCKET)
+ {
+ sck->m_error = GSOCK_IOERR;
+ return GSOCK_IOERR;
+ }
+
+ ioctlsocket(sck->m_fd, FIONBIO, (u_long FAR *) &arg);
+ _GSocket_Enable_Events(sck);
+
+ /* Bind to the local address,
+ * and retrieve the actual address bound.
+ */
+ if ((bind(sck->m_fd, sck->m_local->m_addr, sck->m_local->m_len) != 0) ||
+ (getsockname(sck->m_fd,
+ sck->m_local->m_addr,
+ &sck->m_local->m_len) != 0))
+ {
+ closesocket(sck->m_fd);
+ sck->m_fd = INVALID_SOCKET;
+ sck->m_error = GSOCK_IOERR;
+ return GSOCK_IOERR;
+ }
+
+ return GSOCK_NOERROR;
+}
+
+
/* Generic IO */
/* Like recv(), send(), ... */
assert(socket != NULL);
+ /* Reenable INPUT events */
socket->m_detected &= ~GSOCK_INPUT_FLAG;
if (socket->m_fd == INVALID_SOCKET || socket->m_server)
if (ret == SOCKET_ERROR)
{
- /* NOTE: Window sockets exhibit a very strange property;
- * if the socket is in non-blocking mode (which is always
- * the case here, no matter the setting of GSocket itself)
- * a call to send() can fail with EWOULDBLOCK even when
- * select() says that the socket is writable.
- *
- * This can break several things because, usually, if
- * select() says that the socket is writable, it is
- * assumed that send() won't fail. To avoid this, we
- * return 0 instead of -1 for this special case.
- *
- * XXX - this comment seems not to belong here, and also
- * the code is not consistent with the unix version of
- * gsocket... what to do? (GRG)
- */
if (WSAGetLastError() != WSAEWOULDBLOCK)
- {
socket->m_error = GSOCK_IOERR;
- return -1;
- }
else
- {
socket->m_error = GSOCK_WOULDBLOCK;
- return 0;
- }
+ return -1;
}
return ret;
if (_GSocket_Output_Timeout(socket) == GSOCK_TIMEDOUT)
return -1;
- /* Read the data */
+ /* Write the data */
if (socket->m_stream)
ret = _GSocket_Send_Stream(socket, buffer, size);
else
else
socket->m_error = GSOCK_WOULDBLOCK;
+ /* Only reenable OUTPUT events after an error (just like WSAAsyncSelect
+ * does). Once the first OUTPUT event is received, users can assume
+ * that the socket is writable until a read operation fails. Only then
+ * will further OUTPUT events be posted.
+ */
socket->m_detected &= ~GSOCK_OUTPUT_FLAG;
return -1;
}
* check for the events specified in the 'flags' parameter, and
* it will return a mask indicating which operations can be
* performed. This function won't block, regardless of the
- * mode (blocking|nonblocking) of the socket.
+ * mode (blocking | nonblocking) of the socket.
*/
GSocketEventFlags GSocket_Select(GSocket *socket, GSocketEventFlags flags)
{
assert(socket != NULL);
- return (flags & socket->m_detected);
+ return flags & socket->m_detected;
}
-/* Flags */
+/* Attributes */
/* GSocket_SetNonBlocking:
- * Sets the socket to non-blocking mode. This is useful if
- * we don't want to wait.
+ * Sets the socket to non-blocking mode. All IO calls will return
+ * immediately.
*/
void GSocket_SetNonBlocking(GSocket *socket, bool non_block)
{
}
/* GSocket_SetTimeout:
- * Sets the timeout for blocking calls. Time is
- * expressed in milliseconds.
+ * Sets the timeout for blocking calls. Time is expressed in
+ * milliseconds.
*/
void GSocket_SetTimeout(GSocket *socket, unsigned long millis)
{
}
/* GSocket_GetError:
- * Returns the last error occured for this socket.
+ * Returns the last error occured for this socket. Note that successful
+ * operations do not clear this back to GSOCK_NOERROR, so use it only
+ * after an error.
*/
GSocketError GSocket_GetError(GSocket *socket)
{
return socket->m_error;
}
+
/* Callbacks */
-/* Only one callback is possible for each event (INPUT, OUTPUT, CONNECTION
- * and LOST). The callbacks are called in the following situations:
- *
- * INPUT: There is at least one byte in the input buffer
- * OUTPUT: The system is sure that the next write call will not block
- * CONNECTION: Two cases are possible:
- * Client socket -> the connection is established
- * Server socket -> a client requests a connection
- * LOST: The connection is lost
- *
- * An event is generated only once and its state is reseted when the
- * relative IO call is requested.
- * For example: INPUT -> GSocket_Read()
- * CONNECTION -> GSocket_Accept()
+/* GSOCK_INPUT:
+ * There is data to be read in the input buffer. If, after a read
+ * operation, there is still data available, the callback function will
+ * be called again.
+ * GSOCK_OUTPUT:
+ * The socket is available for writing. That is, the next write call
+ * won't block. This event is generated only once, when the connection is
+ * first established, and then only if a call failed with GSOCK_WOULDBLOCK,
+ * when the output buffer empties again. This means that the app should
+ * assume that it can write since the first OUTPUT event, and no more
+ * OUTPUT events will be generated unless an error occurs.
+ * GSOCK_CONNECTION:
+ * Connection succesfully established, for client sockets, or incoming
+ * client connection, for server sockets. Wait for this event (also watch
+ * out for GSOCK_LOST) after you issue a nonblocking GSocket_Connect() call.
+ * GSOCK_LOST:
+ * The connection is lost (or a connection request failed); this could
+ * be due to a failure, or due to the peer closing it gracefully.
*/
/* GSocket_SetCallback:
{
int count;
- assert (socket != NULL);
+ assert(socket != NULL);
for (count = 0; count < GSOCK_MAX_EVENT; count++)
{
*/
void GSocket_UnsetCallback(GSocket *socket, GSocketEventFlags flags)
{
- int count = 0;
+ int count;
assert(socket != NULL);
/* Internals */
/* _GSocket_Enable_Events:
- * We enable all event notifications here (we need to be notified
- * of all events for internal processing) but we will only notify
- * users when an appropiate callback function has been installed.
+ * Enable all event notifications; we need to be notified of all
+ * events for internal processing, but we will only notify users
+ * when an appropiate callback function has been installed.
*/
void _GSocket_Enable_Events(GSocket *socket)
{
/* OK, we can now leave the critical section because we have
* already obtained the callback address (we make no further
- * accesses to socket->whatever)
+ * accesses to socket->whatever). However, the app should
+ * be prepared to handle events from a socket that has just
+ * been closed!
*/
LeaveCriticalSection(&critical);
return GSOCK_NOERROR;
}
+/* _GSocket_Connect_Timeout:
+ * For blocking sockets, wait until the connection is
+ * established or fails, or until timeout ellapses.
+ */
+GSocketError _GSocket_Connect_Timeout(GSocket *socket)
+{
+ fd_set writefds;
+ fd_set exceptfds;
+
+ FD_ZERO(&writefds);
+ FD_ZERO(&exceptfds);
+ FD_SET(socket->m_fd, &writefds);
+ FD_SET(socket->m_fd, &exceptfds);
+ if (select(0, NULL, &writefds, &exceptfds, &socket->m_timeout) == 0)
+ {
+ socket->m_error = GSOCK_TIMEDOUT;
+ return GSOCK_TIMEDOUT;
+ }
+ if (!FD_ISSET(socket->m_fd, &writefds))
+ {
+ socket->m_error = GSOCK_IOERR;
+ return GSOCK_IOERR;
+ }
+
+ return GSOCK_NOERROR;
+}
+
int _GSocket_Recv_Stream(GSocket *socket, char *buffer, int size)
{
return recv(socket->m_fd, buffer, size, 0);
GSocketError _GAddress_Init_INET(GAddress *address)
{
- address->m_len = sizeof(struct sockaddr_in);
+ address->m_len = sizeof(struct sockaddr_in);
address->m_addr = (struct sockaddr *) malloc(address->m_len);
if (address->m_addr == NULL)
{
address->m_family = GSOCK_INET;
address->m_realfamily = PF_INET;
((struct sockaddr_in *)address->m_addr)->sin_family = AF_INET;
- ((struct sockaddr_in *)address->m_addr)->sin_addr.s_addr = INADDR_NONE;
+ ((struct sockaddr_in *)address->m_addr)->sin_addr.s_addr = INADDR_ANY;
return GSOCK_NOERROR;
}
/* It is a real name, we solve it */
if ((he = gethostbyname(hostname)) == NULL)
{
+ /* addr->s_addr = INADDR_NONE just done by inet_addr() above */
address->m_error = GSOCK_NOHOST;
return GSOCK_NOHOST;
}
return GSOCK_NOERROR;
}
+GSocketError GAddress_INET_SetAnyAddress(GAddress *address)
+{
+ return GAddress_INET_SetHostAddress(address, INADDR_ANY);
+}
+
GSocketError GAddress_INET_SetHostAddress(GAddress *address,
unsigned long hostaddr)
{
if (!port)
{
address->m_error = GSOCK_INVPORT;
- return GSOCK_INVOP;
+ return GSOCK_INVPORT;
}
se = getservbyname(port, protocol);
#else /* !wxUSE_SOCKETS */
/*
- * translation unit shouldn't be empty, so include this typedef to make the
+ * Translation unit shouldn't be empty, so include this typedef to make the
* compiler (VC++ 6.0, for example) happy
*/
typedef (*wxDummy)();
#endif /* wxUSE_SOCKETS || defined(__GSOCKET_STANDALONE__) */
-
-/* Diferencias con la version Unix:
- * - El descriptor es SOCKET y no int
- * - Constantes -1 pasan a INVALID_SOCKET
- * - Errores en muchas funciones pasan de -1 o <0 a SOCKET_ERROR
- * - ioctl y close pasan a ioctlsocket y closesocket
- * - inet_addr en lugar de inet_aton
- * - Codigo de inicializacion y terminacion para inicializar y
- * terminar WinSocket y para la ventana interna.
- * - SetTimeout, SetNonBlocking y la implementacion de los
- * timeouts eran bastante diferentes, pero ahora se han
- * hecho en la version Unix igual que en esta.
- */