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Re: tn3270, mset and map3270

On Sun, Mar 14, 2010 at 10:17:34PM +0000, Christos Zoulas wrote:
> >Right.  That's a botch in the tty interface, in that there is no value
> >for that field for "there is no serial line backing this tty; speed
> >figures are meaningless".  You almost certainly can transfer data
> >through that pty substantially faster than 38400 bits per second.
> Not that simple; ttys should behave consistently. For example, a program
> expects that the tty will hangup when setting speed to 0, and ptys obey
> that currently.

Also, setting speeds on ptys is not a NOP; it depends on what the
software driving the PTY side does with it. I wrote a serial port module for
a hardware emulator (pkgsrc/emulators/gpsim-ptyusart),
and the emulated hardware speed is the speed set on the
tty side (exactly as it would when using real hardware and a NULL-modem
cable to one of the PC COM ports).

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference

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