ImapConnect Function  
 
HCLIENT WINAPI ImapConnect(
  LPCTSTR lpszHostName,  
  UINT nRemotePort,  
  UINT nTimeout,  
  DWORD dwOptions,  
  LPSECURITYCREDENTIALS lpCredentials  
);

The ImapConnect function is used to establish a connection with the server. It supports connection options beyond those provided beyond ImapConnect.

Parameters

lpszHostName
A pointer to a null terminated string which specifies the host name or IP address of the IMAP server.
nRemotePort
The port number the client should use to establish the connection. A value of zero specifies that default port 143 should be used, which is the standard port number assigned to the IMAP service. If the secure port number is specified, an implicit SSL/TLS connection will be established by default.
nTimeout
The number of seconds that the client will wait for a response from the server before failing the current operation.
dwOptions
An unsigned integer value which specifies one or more options. This parameter is constructed by using a bitwise operator with any of the following values:
Constant Description
IMAP_OPTION_NONE No connection options specified. A standard connection to the server will be established using the specified host name and port number.
IMAP_OPTION_IDENTIFY This option specifies that the client should identify itself to the server. If enabled, the client will send the ID command to the server as defined in RFC 2971. This option has no effect if the server does not support the ID command.
IMAP_OPTION_TUNNEL This option specifies that a tunneled TCP connection and/or port-forwarding is being used to establish the connection to the server. This changes the behavior of the client with regards to internal checks of the destination IP address and remote port number, default feature selection and how the connection is established.
IMAP_OPTION_TRUSTEDSITE This option specifies that the server is trusted. The server certificate will not be validated and the connection will always be permitted. This option only affects connections using either the SSL or TLS protocols.
IMAP_OPTION_SECURE This option specifies that a secure connection should be established with the server and requires that the server support either the SSL or TLS protocol. This option is the same as specifying IMAP_OPTION_SECURE_EXPLICIT, which initiates the secure session using the STARTTLS command.
IMAP_OPTION_SECURE_EXPLICIT This option specifies that the client should attempt to establish a secure connection with the server. Note that the server must support secure connections using either the SSL or TLS protocol.
IMAP_OPTION_SECURE_IMPLICIT This option specifies that the client should attempt to establish a secure connection with the server. The server must support secure connections using either the SSL or TLS protocol, and the secure session must be negotiated immediately after the connection has been established.
IMAP_OPTION_FREETHREAD This option specifies that the handle returned by this function may be used by any thread, and is not limited to the thread which created it. The application is responsible for ensuring that access to the handle is synchronized across multiple threads.
lpCredentials
A pointer to a SECURITYCREDENTIALS structure which is used to establish the client credentials for a secure connection to the server. The function ImapCreateSecurityCredentials can be used to create this structure if necessary. If a standard non-secure connection is being established, or client credentials are not required by the server, this parameter can be NULL.

Return Value

If the function succeeds, the return value is a handle to a client session. If the function fails, the return value is INVALID_CLIENT. To get extended error information, call ImapGetLastError.

The dwOptions argument can be used to specify the threading model that is used by the library when a connection is established. By default, the handle is initially attached to the thread that created it. From that point on, until the it is released, only the owner may call functions using that handle. The ownership of the handle may be transferred from one thread to another using the ImapAttachThread function.

Specifying the IMAP_OPTION_FREETHREAD option enables any thread to call any function using the handle, regardless of which thread created it. It is important to note that this option disables certain internal safety checks which are performed by the library and may result in unexpected behavior unless access to the handle is synchronized. If one thread calls a function in the library, it must ensure that no other thread will call another function at the same time using the same handle.

Requirements

Client: Requires Windows 7, Windows Vista or Windows XP.
Server: Requires Windows Server 2008 or Windows Server 2003.
Header: Include cstools7.h.
Library: Use csmapav7.lib.
Unicode: Implemented as Unicode and ANSI versions.

See Also

ImapAsyncConnect, ImapDisconnect, ImapInitialize, ImapLogin