InternetDial function (winineti.h)

Initiates a connection to the Internet using a modem.

Syntax

DWORD InternetDial(
  [in]  HWND    hwndParent,
  [in]  LPSTR   lpszConnectoid,
  [in]  DWORD   dwFlags,
  [out] LPDWORD lpdwConnection,
  [in]  DWORD   dwReserved
);

Parameters

[in] hwndParent

Handle to the parent window.

[in] lpszConnectoid

Pointer to a null-terminated string that specifies the name of the dial-up connection to be used. If this parameter contains the empty string (""), the user chooses the connection. If this parameter is NULL, the function connects to the autodial connection.

[in] dwFlags

Options. This parameter can be one of the following values.

Value Meaning
INTERNET_AUTODIAL_FORCE_ONLINE
Forces an online connection.
INTERNET_AUTODIAL_FORCE_UNATTENDED
Forces an unattended Internet dial-up. If user intervention is required, the function will fail.
INTERNET_DIAL_FORCE_PROMPT
Ignores the "dial automatically" setting and forces the dialing user interface to be displayed.
INTERNET_DIAL_UNATTENDED
Connects to the Internet through a modem, without displaying a user interface, if possible. Otherwise, the function will wait for user input.
INTERNET_DIAL_SHOW_OFFLINE
Shows the Work Offline button instead of the Cancel button in the dialing user interface.

[out] lpdwConnection

Pointer to a variable that specifies the connection number. This number is a unique identifier for the connection that can be used in other functions, such as InternetHangUp.

[in] dwReserved

This parameter is reserved and must be NULL.

Return value

Returns ERROR_SUCCESS if successful, or an error value otherwise. The error code can be one of the following values.

Return code Description
ERROR_INVALID_PARAMETER
One or more of the parameters are incorrect.
ERROR_NO_CONNECTION
There is a problem with the dial-up connection.
ERROR_USER_DISCONNECTION
The user clicked either the Work Offline or Cancel button on the Internet connection dialog box.

Remarks

InternetDial does not support double-dial connections, SmartCard authentication, or connections that require registry-based certification.

Note  Starting on Windows Vista and Windows Server 2008, the WinINet dial-up functions use the RAS functions to establish a dial-up connection. WinINet supports the functionality documented in the RasDialDlg function.
 
Like all other aspects of the WinINet API, this function cannot be safely called from within DllMain or the constructors and destructors of global objects.
Note  WinINet does not support server implementations. In addition, it should not be used from a service. For server implementations or services use Microsoft Windows HTTP Services (WinHTTP).
 

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header winineti.h (include Wininet.h, Winineti.h, Wininet.h, Winineti.h)
Library Wininet.lib
DLL Wininet.dll

See also

Establishing a Dial-Up Connection to the Internet

WinINet Functions