# Sending overlapped digits

Some signaling protocols such as ISDN support overlapped sending of digits: the sending of address information in multiple bursts, rather than all at once. The application can call nccQueryCapability to determine if the protocol supports this feature.

The application supplies the first digit or digits when invoking nccPlaceCall. When the application enters the placing call state (see Monitoring the placing call state), it invokes the nccSendDigits function repeatedly to send additional segments of the digit string, in order. If the digit string sent by an invocation of either function is not the final one, the final character in the string should be a ~, signifying to the protocol that more digits will follow. The final digit string should not include the final ~ character. For example:

nccPlaceCall 172~
nccSendDigits 57924~
nccSendDigits 5~
nccSendDigits 28

Final digit string: 17257924528

Note: The overlapped sending feature is not available for the LPS, OPS, and GDS protocols.