How to replace MS DOS serial (RS232) printer with a computer

We have a legacy data acquisition system running on MS DOS, which prints recorded data to a Serial RS232 printer. I replaced the serial printer with industrial computer using NULL modem cable. Upon sending print command from MS DOS application, application prompts "Printer Error". Is there any handshaking mechanism which first detects the printer on serial port and only then sends data to serial port? How can I implement this task.
Or is there any way out to write the print data to a text file, which I can retrieve when needed.