[net.unix] Info sought on sending ascii NULL on output

haynes@hao.UUCP (Dan Haynes) (03/05/85)

I was trying to download some graphics commands from a Vax 4.2 system
to an inkjet printer over a tty line.  This particular printer requires
a special sequence to put it in graphics mode; one of the characters in
this sequence is an ascii null.  All attempts thus far to get a null
char output have failed.  There does not seem to be any problem outputting
any other control char (in RAW mode).  If anyone can provide me with
a clue to a method to get a null on output, please send me mail.

Thanks in advance,
Dan Haynes
haynes%ncar@csnet-relay.arpa	ARPA
haynes@ncar.csnet		CSNET
hao!haynes			UUCP

haynes@hao.UUCP (Dan Haynes) (03/08/85)

> I was trying to download some graphics commands from a Vax 4.2 system
> to an inkjet printer over a tty line.  This particular printer requires
> a special sequence to put it in graphics mode; one of the characters in
> this sequence is an ascii null.  All attempts thus far to get a null
> char output have failed.  There does not seem to be any problem outputting
> any other control char (in RAW mode).  If anyone can provide me with
> a clue to a method to get a null on output, please send me mail.

I have solved the "no nulls on output over a tty line" problem.
It turned out that the particular terminal I was testing this on,
a Wyse 50, treats nulls as a no-op even in MONITOR mode.  Hooking
a scope up to the receive line proved this.

Dan Haynes
haynes%ncar@csnet-relay.arpa	ARPA
haynes@ncar.csnet		CSNET
hao!haynes			UUCP