Re: Re: Menu on bootup?

On Mon, 17 Oct 2011, Nevyn wrote:
> exec </dev/console >/dev/console 2>&1
> The script stuff is fairly trivial. I've never really understood file
> descriptors. Is anyone able to explain that first line to me?
>
> exec </dev/console >/dev/console 2>&1

The "exec" built-in is a bit funny. Unlike most shell commands where if you
preface a variable-setting or set some I/O-redirection they only apply to
just that one command, for "exec" (without a filename) they remain in effect
for the rest of the script or shell session. (Using "exec" *with* a filename
results in the current shell session being *replaced by* that other
program.)

In this case it means connect the stdin and stdout each to /dev/console, and
then connect stderr to wherever stdout is connected.

/dev/console is a generic device that starts out meaning /dev/tty1, but can
be redirected to an xconsole, or into syslog, or wherever is useful.

Not sure why they'd bother connecting stdin, unless they expect that
something might possibly need keyboard input, and that would only work if
it's still connected to /dev/tty1. It would be shorter and more appropriate
to write

 exec </dev/null >/dev/console 2>&1

-Martin

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