The "BUFSIZE" parameter specifies the size of the buffer for DOS versions of Business Rules. The default is 2000 bytes, which is low for high-speed data transmission. To avoid losing data with rates of 2400 bps or higher; an increased BUFSIZE is recommended.
In Business Rules, Unix and Linux versions ignore the BUFSIZE parameter, as the operating systems handle the buffering for these versions instead.
See this parameter in Open Communications.