CmAcquireConnection (Compact 7)
3/12/2014
This function acquires a connection to use.
Syntax
CM_RESULT CmAcquireConnection(
__in CM_CONNECTION_HANDLE hConnection
);
Parameters
- hSession
[in] A pointer to a CM_SESSION_HANDLE.
Return Value
The following table shows possible return values.
Value | Description |
---|---|
CMRE_SUCCESS |
The operation completed successfully. |
CMRE_INVALID_CONNECTION |
The name of the connection is not valid. |
CMRE_CONNECTION_ALREADY_ACQUIRED |
A connection has already been established in the context of this session. |
CMRE_UNEXPECTED |
An unexpected failure occurred. |
Remarks
Only one connection can be acquired in the context of a single session.
Selected Windows Sockets (Winsock) and Windows Internet (WinINet) APIs can automatically connect a SOCKET or HINTERNET handle to the requested destination host.
Avoiding Synchronization Problems when Establishing a Connection
After you call CmAddConnectionConfig to add a connection, the connection will be in CMCS_DISCONNECTED_UNAVAILABLE state for a short period of time. If during this time CmAcquireConnection is called, it would fail with a general error code. To avoid this problem, wait until the connection is in CMCS_DISCONNECTED state, and then call CmAcquireConnection.
Set Priorities Explicitly when Switching Connections
When you have a CMCB_ALWAYS_CONNECTED connection that is using a unique resource, such as the only Wi-Fi card in the device, and you want to switch to another connection that needs the same resource, you must make sure that your client session has a higher priority than the CMCB_ALWAYS_CONNECTED connection.
A CMCB_ALWAYS_CONNECTED connection has a priority of CM_PRIORITY_BACKGROUND_LOWEST. The default priority of the new connection is lower than that. This means that when you create your session you must explicitly call CmSetPriority with a higher priority than CM_PRIORITY_BACKGROUND_LOWEST.
Requirements
Header |
cmnet.h |
Library |
cmnet.lib |
See Also
Reference
Connection Manager Connectivity Functions
CM_CONNECTION_STATE
CM_CONNECTION_CONNECT_BEHAVIOR
CM_PRIORITY
CmSetPriority