fork/exec & close file descriptors

[Alain Ketterlin]

Chris Angelico <rosuav at gmail.com> writes:

> On Wed, Jun 3, 2015 at 7:06 AM, Alain Ketterlin
> <alain at universite-de-strasbourg.fr.invalid> wrote:
>> I've no idea what the OP's program was doing, so I'm not going to split
>> hairs. I can't imagine why one would like to mass-close an arbitrary set
>> of file descriptors, and I think APIs like os.closerange() are toxic and
>> an appeal to sloppy programming.
>
> When you fork, you get a duplicate referent to every open file in both
> parent and child. [...]

Thank you, I know this. What I mean is: what are the reasons that you
cannot access your file descriptors one by one? To me closing a range of
descriptors has absolutely no meaning, simply because ranges have no
meaning for file descriptors (they're not ordered in any way). What if
some library uses its own descriptors that happen to lie in your
"range"? Etc.

-- Alain.