Re: No such device or address when opening /dev/fd/<x> on opened /dev/tcp socket

[Oğuz]

5 Nisan 2021 Pazartesi tarihinde Oğuz <oguzismailuysal@gmail.com> yazdı:

> 5 Nisan 2021 Pazartesi tarihinde Chet Ramey <chet.ramey@case.edu> yazdı:
>
>> On 4/5/21 3:14 PM, Oğuz wrote:
>>
>>> 5 Nisan 2021 Pazartesi tarihinde Chet Ramey <chet.ramey@case.edu
>>> <mailto:chet.ramey@case.edu>> yazdı:
>>>
>>>     There's no guarantee that file descriptors opened with socket(2)
>>> show up in
>>>     /dev/fd. Bash doesn't emulate /dev/fd if the system provides it, so
>>> it's up
>>>     to the OS on those systems whether they do or not.
>>>
>>>     It doesn't generate that error on macOS, for instance, which has
>>> /dev/fd.
>>>
>>>
>>> I can reproduce the error, but it is coming from `tee', which tries to
>>> open `/dev/fd/??' as a regular file whereas it is a socket, and gets an
>>> ENXIO error.
>>>
>>
>> That's what I mean. What happens on a system that implements /dev/fd and N
>> in /dev/fd/N is a valid descriptor? There are varying answers.
>>
>> The simplest /dev/fd drivers just dup the file descriptor passed as an
>> argument. There are progressively more complex implementations. It's
>> not guaranteed they treat descriptors returned by socket(2) the same as
>> those returned by open(2), even to whether they show up in /dev/fd at all.
>>
>> If you don't have /dev/fd, all bets are off, of course, but then I'd guess
>> the error would be ENOENT.
>
>
> Yeah. If you have /dev/fd though you have /dev/fd/1 (and even
> /dev/stdout), so OP could have done `echo a | tee /dev/fd/1
> >/dev/tcp/host/port' instead
>

That should have been `echo a | tee /dev/fd/3 3>&1 >/dev/tcp/host/port'


>
>
>>
>> --
>> ``The lyf so short, the craft so long to lerne.'' - Chaucer
>>                  ``Ars longa, vita brevis'' - Hippocrates
>> Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/
>>
>
>
> --
> Oğuz
>
>

-- 
Oğuz