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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: O_NOCTTY flag sticky under Cygwin
Date: Tue, 8 May 2001 17:40:54 +0400
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It appears, that O_NOCTTY is sticky. I.e. if a tty was opened with this flag,
it will never become a controlling tty. The following pseudo code:

fd = open("/dev/pts/1", O_RDWR|O_NOCTTY);
close(0);
close(1);
close(2);
dup2(fd,0);

does not make /dev/pts/1 controlling tty under Cygwin. It does it on most
major Unix flavours (Solaris, Linux, BSD, AIX, HP-UX).

If I understand SUS V2 correctly, this flag applies only to open() call
itself:

O_NOCTTY
If set and path identifies a terminal device, open() will not cause the
terminal device to become the controlling terminal for the process.

-andrej

Have a nice DOS!
B >>


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