[PATCH] cttyhack: print detected ctty name when called without parameters

Alexander Shishkin virtuoso at slind.org
Mon Oct 31 15:10:49 UTC 2011


On Mon, 31 Oct 2011 13:21:01 +0100, Denys Vlasenko <vda.linux at googlemail.com> wrote:
> On Mon, Oct 31, 2011 at 12:25 PM, Denys Vlasenko
> <vda.linux at googlemail.com> wrote:
> > On Mon, Oct 31, 2011 at 1:15 AM, Alexander Shishkin <virtuoso at slind.org> wrote:
> >> Sometimes there's a need to figure out the controlling tty from a shell
> >> script, for example, to obtain a line for getty.
> >> In this case it's easier
> >> to call cttyhack than trying to repeat some of the cttyhack's logic.
> >
> > "cttyhack getty 0 -" should work, right?
> >
> >
> >> +       /* If it's a /dev/tty, still make sure it's wired to std{in,out,err} */
> >> +       fd = open_or_warn(console, O_RDWR);
> >> +       if (fd < 0)
> >> +               goto ret;
> >> +       //bb_error_msg("switching to '%s'", console);
> >> +       dup2(fd, STDIN_FILENO);
> >> +       dup2(fd, STDOUT_FILENO);
> >> +       xmove_fd(fd, STDERR_FILENO);
> >
> > Think what would happen if fd = 1
> 
> Fixed it and applied to git. Thanks.

Thanks, except for now there is a problem with the serial test going
before the sysfs test, and the former is almost never accurate as very
few serial drivers use "ttyS" names these days. I'd say that the sysfs
test is the most relevant for the cttyhack purposes.

Regards,
--
Alex



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