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From: "Andrej Borsenkow" <Andrej DOT Borsenkow AT mow DOT siemens DOT ru>
To: "Cygwin Mailing List" <Cygwin AT Sourceware DOT Cygnus DOT Com>
Subject: Possible bug with select and master side of pty
Date: Wed, 8 Nov 2000 17:46:06 +0300
Message-ID: <000001c04992$9ff5e8c0$21c9ca95@mow.siemens.ru>
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When polling master side of pseudo tty for reading, select is just using
common function fhandler_pipe::select_read. This does not work when we do
onlcr conversion (actually, always), read buffer of size 1 and are reading NL.
In this case, first select returns readable descriptor (because there is real
data in master-slave pipe) and first read returns CR. Second select does not
think fd is readable because there is no more data in pipe; still, read from
master side would return NL here.

It _looks_ like adding fhandler_tty_master::select_read that is combination of
fhandler_tty_common::select_read (when need_nl == 0) and
fhandler_null::select_read (when need_nl != 0) should do the job. But I never
programmed in C++ and do not trust myself to fully understand all these method
interaction :(

-andrej

Have a nice DOS!
B >>


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