In Blueworx Voice Response channels are numbered from SL_MIN_CHANNEL_ID (currently set to 1) through SL_MAX_CHANNEL_ID1 (currently set to 30); packs are numbered from SL_MIN_TRUNK_ID1 (currently set to 1) through SL_MAX_TRUNK_ID1(currently set to 16). Both are type int. This 1-based numbering scheme is used for consistency with general telephony numbering of trunks and channels, the Blueworx Voice Response user interface, and the custom server programming interface.
The signaling interface specifies structures that are able to handle the maximum number of packs and channels that Blueworx Voice Response can support. An individual Blueworx Voice Response system may not be configured with this capacity. For example, a T1 system can have a maximum of 24 channels available on a trunk. The signaling process should be designed to support the maximum number of packs and channels as defined in the signaling interface. The signaling process should make use of the sl_query_sigproc() subroutine to determine which subset of channels and packs it controls at run time.
The signaling interface specifies two special values, SL_UNDEFINED_VPACK and SL_UNDEFINED_CHAN, which should be used when a pack or channel is unknown.