The Postscript port on the LaserWriter Pro 810 is defined as port 3107. You can find the port definition of the other ports by taking the printer off line and telling it to print a status page.
The following is the printcap file from a Sun computer. The Printer is called 'reams' and it is the 8th printer defined in the printcap. Replace 'reams' with the name of your printer in the appropriate place if you want to print Postscript from Unix to the LaserWriter Pro 810.
# ** |reams8| entry maintained by Apple Printer Installation Program **
# printer type =PRO810
# printer interface type =Ethernet
# printer physical port number =1
reams8|reams8|Apple remote printer on port 1:\\
:lp=/dev/reams8:\\
:sd=/usr/spool/reams8:\\
:of=/home/software/apple/bin/apprint:\\
:mx#0:\\
:sf:\\
:sh:\\
:pw#0:\\
:apple_n=17.127.4.47:\\
:apple_pcs=:\\
:apple_scs=:\\
:apple_text=disable:\\
:apple_p=3107:
It is important to note the apple_text=disable and the apple_p=3107. Now any job printed to the Reams8 print queue will be printed as a Postscript job.
In order to print a Postscript file once this printcap is in place you should type lpr -P reams8 <filename>.