pty.7: Clarify asynchronous nature of PTY I/O
commit4b06376957c568646b3d94d0075013b7871d35f6
authorNeilBrown <neilb@suse.de>
Tue, 5 May 2015 22:59:07 +0000 (6 08:59 +1000)
committerMichael Kerrisk <mtk.manpages@gmail.com>
Thu, 7 May 2015 08:24:51 +0000 (7 10:24 +0200)
tree77778fa865ac7ad79037c86b206d960604e66742
parentec9a2be0f9751893a1c1e1e1e7ca5be069b5869c
pty.7: Clarify asynchronous nature of PTY I/O

A PTY is not like a pipe - there may be delayed between data
being written at one end and it being available at the other.

This became particularly apparent after
     commit f95499c3030f
    ("n_tty: Don't wait for buffer work in read() loop")
in Linux 3.12

See also the mail thread at https://lkml.org/lkml/2015/5/1/35
Date Mon, 04 May 2015 12:32:04 -0400
From Peter Hurley <>
Subject Re: [PATCH bisected regression] input_available_p()
                sometimes says 'no' when it should say 'yes'

Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
man7/pty.7