My understanding of the printer problem leads to believe this is not terribly easy.
If every program out there uses the BIOS interrupts to send data to the printer, then it is pretty easy - you install a handler to intercept the BIOS calls and buffer the outgoing data elsewhere. The outgoing data then gets sent via a network to the printer. A TSR is not really even needed; you can have a standard program do this, shell to DOS, and then run the program to be intercepted from there. Not as convenient as a TSR, but much easier for debugging. However, if a program "bit bangs" the parallel port directly you can't capture that output. I don't know of any technique that allows one to intercept raw port I/O commands, unless you are running in a virtual machine (virtual 8086 mode included). Then the host operating system technically can intercept raw port I/O. The mTCP netcat program can be used to send the contents of a file straight to a printer. I think the HP JetDirect stuff (often found on other printers) is pretty crude; it is just an open port and there is no protocol or handshaking required. Mike ------------------------------------------------------------------------------ _______________________________________________ Freedos-devel mailing list Freedos-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-devel
