Does printing require a separate process?

[Ron Kaplan]

I noticed that HARDCOPYW does an ADD.PROCESS around the printer's sending function, but SEND.FILE.TO.PRINTER just invokes the sending function directly.

They probably should do it the same way. Is there any current motivation for the complexity of the separate process in the generic code? If it is an important thing to do for particular classes of printers, maybe that should be in the printer-specific SEND method.

[Herb Jellinek]

Some printers (Epson MX-80, Xerox 4045, etc.) were attached directly to the D-machine via parallel port and were quite slow relative to, say, a networked laser printer.  Having client code block until the printer completed an entire document would have provided a terrible user experience.  I don't know why HARDCOPYW rather than SEND.FILE.TO.PRINTER called ADD.PROCESS.  Maybe it was an arbitrary choice.

Of course, a networked printer can take an arbitrarily long time to receive a document, so maybe we should just assume that print jobs should never block and put the ADD.PROCESS call in the most generic/high level hardcopy code.

            Herb