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Chapter 6 - Sequence Grabber Channel Components / Sequence Grabber Channel Components Reference

Functions / Working With Channel Devices

SGGetChannelDeviceList

The SGGetChannelDeviceList function allows the sequence grabber to retrieve a list of the devices that are valid for your channel.

pascal ComponentResult SGGetChannelDeviceList (SGChannel c, 
                                             long selectionFlags, 
                                             SGDeviceList *list);

c

Identifies the channel connection for this operation.

selectionFlags

Controls the data you are to return for each device. The following flags are defined:

sgDeviceListWithIcons

Specifies whether the sequence grabber wants to retrieve an icon for each device. If this flag is set to 1, return an icon for each device in the list, in the icon field. If this flag is set to 0, set the icon field to 0.

sgDeviceListDontCheckAvailability

Controls whether you verify that each device is
currently available. If this flag is set to 1, do not
check the availability of each device. Otherwise, you should check each device's availability, and set the sgDeviceNameFlagDeviceUnavailable flag appropriately in each device name structure that you return.

list

Contains a pointer to a device list structure pointer. The channel creates a device name structure and returns a pointer to that structure in the field referred to by this parameter. Applications use the sequence grabber's SGDisposeDeviceList function to dispose of the memory used by
the list.

DESCRIPTION

This function allows the sequence grabber to retrieve a list of the devices that may be used by your channel. Each entry in this list identifies a valid device by name. Applications may then place these device names into a menu using the sequence grabber's SGAppendDeviceListToMenu function.

Applications may use this function in order to determine the device your channel is currently using. Be sure to set the selectedIndex field properly.

RESULT CODES

Memory Manager errors

SEE ALSO

You may use the sequence grabber's SGSortDeviceList function to sort the entries
in your device list structure. This function is discussed on page 6-86.