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3.2 Opening a Switch Handle

swiOpenSwitch opens a switching device and creates a context for subsequent switching calls. The handle is used to refer to the switch block in the Switching service functions.
A switch handle is always associated with a CTA context. When you specify a switch handle, the CTA context is implied as illustrated in Figure 5. Figure 5. A Switch Handle Associated With a CTA Context
You cannot open an MVIP switch block in one CTA context and then refer to it in another CTA context. Note: If you have multiple threads, each with its own CTA context, and you want to make connections on a switch block, each thread must obtain its own switch handle for the switch block.
To open a switch handle: Specify MVIP-90 mode or MVIP-95 mode. Enable terminus output state restoration.

3.2.1 Specifying MVIP-95 or MVIP-90 Mode

Caution:	Since MVIP-95 device drivers can only be opened in MVIP-95 mode, it is recommended that all applications that may use MVIP-95 device drivers in the future, be written to use MVIP-95 mode even if the application is not currently using MVIP-95 device drivers.

When the SWI_ENABLE_RESTORE constant is used as a parameter to swiOpenSwitch, the states of the switch block outputs are saved so that they can be restored when the switch handle is closed using swiCloseSwitch. If you want to use the SWI_ENABLE_RESTORE mode, a single terminus should not be controlled by more than one switch handle. Otherwise, a terminus affected by your application might be restored to a condition set by some other application or to a condition set via a different switch handle in your own application.
swiResetSwitch cannot be called if the switch handle is opened with the SWI_ENABLE_RESTORE constant enabled.

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