Re: [BUG] failure to push/restore closed file descriptor

[Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>]

On Fri, Apr 27, 2018 at 05:47:27PM +0200, Martijn Dekker wrote:
>
> No, because step 1 doesn't merely close fd 8. It enters a curly braces block
> (a compound command) that locally closes fd 8 using a redirection, just like
> any other redirection would be local to that compound command. Thus,
> restoring the fd state when leaving that block must undo the effect of the
> 'exec'.
> 
> Note that dash already does this correctly if the '8<&-' is replaced by any
> other redirection such as '8>/dev/tty'.

That's different as 8 was previously closed and is now open.

> POSIX 2.7 Redirection says: "Redirection is used to open and close files for
> the current shell execution environment [...] or for any command". Note that
> "any command" includes compound commands such as curly braces blocks.

Well, I don't see anything in POSIX that requires us to close fd 8.
Can you please point it out to me please?

Thanks,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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