Very Computer

by **Robert Lupton (the Go** » Sun, 14 Oct 1990 05:29:01

I have some code that runs on lots of machines and reads keystrokes
in CBREAK mode, using a BSD-style tty driver. Compiling with
c89 -D_POSIX_SOURCE -Dunix
I get a delay of 4 key-strokes between when I type a character and when
my code sees and echoes it.

Any ideas?

Robert

by **Kevin P. Kleinfelt** » Tue, 16 Oct 1990 06:24:58

Quote:>I have some code that runs on lots of machines and reads keystrokes
>in CBREAK mode, using a BSD-style tty driver. Compiling with
> c89 -D_POSIX_SOURCE -Dunix
>I get a delay of 4 key-strokes between when I type a character and when
>my code sees and echoes it.

Is NCHARS=5? We found that changing the tty configuration via
stty TCSETA, while characters were present in the buffer, caused the tty
driver to insist on having all NCHARS chars in the input buffer, regardless of
the setting of NDELAY. There is a fix (they created it for us). It is new,
and involves replacing the driver. (Be sure they give you the fixed fix --
the first fix only changed the problem, and did not fix it!)
--

{emory,gatech}!nanovx!msa3b!kevin

"Don't hold your finger on the button if the motor ain't goin' roundy-roundy."

Very Computer

Delay of four characters using CBREAK mode on RS/6000

Delay of four characters using CBREAK mode on RS/6000

Delay of four characters using CBREAK mode on RS/6000