Building Data Streams

When a file arrives on the link, the AXSGET routine calls DMTAXMRQ to open the file. AXSGET then returns control to PROGO, which in turn calls DMTRDREP to get the next file record.

The GETBLOCK routine continues to call DMTRDREP until it obtains all records in the file. GETBLOCK prepares the buffer that is sent to the printer and places the appropriate prefix in the buffer. GETBLOCK calls DMTSEPHD and DMTSEPTR to build any required separator pages. Each record is placed in a transmission buffer. When the buffer is filled, the records are compressed. GETBLOCK then calls the LINEIO routine to send the buffer to the printer. DMTPCRTR formats the records into 3270 data stream format.