SJOBRG.ANDY%MIT-OZ%mit-mc@sri-unix.UUCP (06/25/83)
From:  Andrew Scott Beals <SJOBRG.ANDY%MIT-OZ@mit-mc>
Long long ago, someone asked how to simulate a ^P ...
well, there is a magic location in the BDOS that contains a 1
if the output to the console is to be echoed to the printer,
and a 0 for no echo to the printer...
here are two (bds) c functions to turn the printer echo on
and off:
prt_on() {
	char	*pbyte;
	char	**bdosp;
	bdosp = 6;	/* the jump address into bdos */
	pbyte = *bdosp + 0x307;	/* pbyte now points to the printer flag */
	*pbyte = 1;
}
prt_off() {
	char	*pbyte;
	char	**bdosp;
	bdosp = 6;	/* bdos jump address */
	pbyte = *bdosp + 0x307;
	*pbyte = 1;
}
and now you have it.
this is for cp/m 2.2 only (as far as i know), and i can provide
the same two functions in another language, if you like...
later,
	-andy
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