Getchar w/wout echo

mcdonald at uxe.cso.uiuc.edu mcdonald at uxe.cso.uiuc.edu
Wed Aug 31 23:38:00 AEST 1988


	>Another one of those fine confused wish list discussions.  Unfortunately,
	>like the other discussions of this type,  it is fatally flawed.	
	>The problem is,   evreyone seems to be confusing language functionality
	>with os functionality.  Terminal echo is a function provided by the
	>operating system (in this case,  UNIX(tm)).  Whether or not echoing
	>is going on is invisible to getchar(),  and read.  The tty device driver
	>is controlling this operation,  and only an ioctl can change its
	>behaviour.  In many cases,  the echoing function is not even taking
	>place on the same processor.  In the NCR TOWER(tm) series,  the
	>echoing is being done on the HPSIO (a separate 68010 based processor)
	>and is thereby not burdening the CPU. 


>	Before you go mucking with the language,  I suggest you learn
>	a bit more about your hardware,  your operating system,  and
>	how they interrelate.  Then I suggest you do what I did when I
>	wrote a menuing system - read everything available about the
>	tty device drivers,  stty,  and termio,  experiment like
>	crazy,  then write your own raw character input routines.

We want it put in the language so that programs will run portably,
and MOST IMPORTANTLY, so that operating system designers will
have to fix their operating systems so that it can be done 
portably!!!!!!!!!!

Doug McDonald



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