How to throttle writes according to input queue size of other paired port about tty0tty HOT 3 OPEN

n_tty_chars_in_buffer() in n_tty.c looks promising. I'm not sure if I have to check two buffers. It looks as though there are two stages of buffering --

• The first stage being the buffers in tty_buffers.c. Maybe tty->buf->memory_used is the total of that.
• The second stage being the line discipline buffers in n_tty.c. n_tty_chars_in_buffer() hopefully gives me that.

Is that right or am I misunderstanding?

from tty0tty.

Neither tty->buf->memory_used nor n_tty_chars_in_buffer() seemed to be valid. I've had some success with tty->read_cnt--at least, on 2.6.35 kernel.

from tty0tty.

scenario where the application connected to the other paired port can only read data at a certain rate

https://en.wikipedia.org/wiki/RS-232#RTS,_CTS,_and_RTR a.k.a. hardware flow control.

@cmcqueen consider to close this issue to prevent it consumes further human energy. (Yes, open issues do have some costs)

from tty0tty.