Programming GammaLink fax cards with Fax C++ is slightly different from programming COM ports or Brooktrout cards. Since all GammaLink configuration values are set from the configuration file when the GammaLink dispatcher starts, these values cannot be changed from any of the functions. Also, most of the transmission parameters which are set or returned by COM Port Handler functions are handled by the GammaLink driver internally. Therefore, many of the COM Port Handler functions cannot be called from GammaLink Channels.
Also, because the GammaLink takes the entire fax and sends it at once, it is not possible to forecast fax transmission for pages. There is no way to know at any given time which page is being sent. In the case of fax transmission failure, there is no way of knowing how many pages were successfully sent. When the fax transmission fails, the entire fax will have to be re-sent.
The following members of the structure SessionParameters, which is returned by the function GetSessionParameters, are also invalid: Volume, DialMode, BitOrder, RingToAnswer, Resolution, Width, Compression, ScanLine, dwBytesInPage, dwTransmitBytes, dwTotalTransmitBytes, LineCount. The member ‘Baud’ is valid only after the transmission is finished.
The following functions for GammaLink work only with the 32 bit version of the Fax C++.