| Platform SDK: RAS/Routing and RAS |
The RasDial function establishes a RAS connection between a RAS client and a RAS server. The connection data includes callback and user-authentication information.
DWORD RasDial(
LPRASDIALEXTENSIONS lpRasDialExtensions,
// pointer to function extensions data
LPCTSTR lpszPhonebook, // pointer to full path and file name of
// phone-book file
LPRASDIALPARAMS lpRasDialParams,
// pointer to calling parameters data
DWORD dwNotifierType, // specifies type of RasDial event handler
LPVOID lpvNotifier, // specifies a handler for RasDial events
LPHRASCONN lphRasConn // pointer to variable to receive
// connection handle
);
Windows 95: This parameter is ignored. On Windows 95, RasDial always uses the default behaviors for the RASDIALEXTENSIONS options.
Windows 95: This parameter is ignored. Dial-up networking stores phone-book entries in the registry rather than in a phone-book file.
The caller must set the RASDIALPARAMS structure's dwSize member to sizeof(RASDIALPARAMS) to identify the version of the structure being passed.
| Value | Meaning |
|---|---|
| 0xFFFFFFFF | The lpvNotifier parameter is a handle to a window to receive progress notification messages. In a progress notification message, wParam is the equivalent of the rasconnstate parameter of RasDialFunc and RasDialFunc1, and lParam is the equivalent of the dwError parameter of RasDialFunc and RasDialFunc1.
The progress notification message uses a system registered message code. You can obtain the value of this message code as follows: {UINT unMsg =
RegisterWindowMessageA( RASDIALEVENT );
if (unMsg == 0)
unMsg = WM_RASDIALEVENT;
}
|
| 0 | The lpvNotifier parameter points to a RasDialFunc callback function. |
| 1 | The lpvNotifier parameter points to a RasDialFunc1 callback function. |
| 2 | Windows NT/2000: The lpvNotifier parameter points to a RasDialFunc2 callback function. |
If this parameter is not NULL, RasDial sends the window a message, or calls the callback function, for each RasDial event. Additionally, the RasDial call operates asynchronously: RasDial returns immediately, before the connection is established, and communicates its progress via the window or callback function.
If lpvNotifier is NULL, the RasDial call operates synchronously: RasDial does not return until the connection attempt has completed successfully or failed.
If lpvNotifier is not NULL, notifications to the window or callback function can occur at any time after the initial call to RasDial. Notifications end when one of the following events occurs:
The callback notifications are made in the context of a thread captured during the initial call to RasDial.
If the function succeeds, the immediate return value is zero. In addition, the function stores a handle to the RAS connection into the variable pointed to by lphRasConn.
If the function fails, the immediate return value is a nonzero error value, either from the set listed in the RAS header file or ERROR_NOT_ENOUGH_MEMORY.
Errors that occur after the immediate return can be detected by RasGetConnectStatus. Data is available until an application calls RasHangUp to hang up the connection.
An application must eventually call RasHangUp whenever a non-NULL connection handle is stored into *lphRasConn. This applies even if RasDial returns a nonzero (error) value.
An application can safely call RasHangUp from a RasDial notifier callback function. If this is done, however, the hangup does not occur until the routine returns.
Windows NT/2000: If the structure pointed to by lpRasDialExtensions enables RDEOPT_PausedStates, the RasDial function pauses whenever it enters a state in which the RASCS_PAUSED bit is set to one. To restart RasDial from such a paused state, call RasDial again, passing the connection handle returned from the original RasDial call in *lphRasConn. The same notifier used in the original RasDial call must be used when restarting from a paused state.
Windows 2000: RAS supports referenced connections. If the entry being dialed is already connected, RasDial will return SUCCESS and the connection will be referenced. To disconnect the connection, each RasDial on the connection should be matched by a RasHangUp.
Windows 2000: Because some phone-book entries require Extensible Authentication Protocol (EAP) for authentication, the caller should call RasGetEapUserIdentity before calling RasDial. If RasGetEapUserIdentity returns ERROR_INVALID_ENTRY_FOR_FUNCTION, the phone-book entry does not require EAP. However, if RasGetEapUserIdentity returns NO_ERROR, the caller should copy the EAP identity information from RasGetEapUserIdentity into the RasEapInfo member of RASDIALEXTENSIONS, and the szUserName member of RASDIALPARAMS. See RasGetEapUserIdentity for more information. If the phone-book entry requires EAP, the dwfOptions member of the RASENTRY structure for the entry contains the RASEO_RequireEAP flag.
To specify that RasDial should enter a RASCS_CallbackSetByCaller state, set lpRasDialParams->szCallbackNumber to "*" on the initial call to RasDial. When your notification handler is called with this state, you can set the the callback number to a number supplied by the user.
Windows 95: Windows 95 does not support the RASCS_CallbackSetByCaller state or any of the other paused states.
Windows NT/2000: Requires Windows NT 3.1 or later.
Windows 95/98: Requires Windows 95 or later.
Header: Declared in Ras.h.
Library: Use Rasapi32.lib.
Unicode: Implemented as Unicode and ANSI versions on Windows NT/2000.
Remote Access Service (RAS) Overview, Remote Access Service Functions, Dialable Addresses, RasDialDlg, RasDialFunc, RasDialFunc1, RasDialFunc2, RasGetConnectStatus, RasHangUp, RASDIALEXTENSIONS, RASDIALPARAMS, WM_RASDIALEVENT