Portability issue of C code

[Erwan MAS <erwan@mas.nom.fr>]

Hi everyone , 

So i try to understand why a package do not work on Hurd .

After a few hours , i was able to isolate  the code, so now i have a very 
simple code that expose the bug , my code is here https://paste.debian.net/plain/1377135 .

The issue is with getline from libc , when reading from a directory instead of a file .

So on Macos,Debian Linux,Alpine,FreeBsd  i have a error ( 21 / Is a directory ) ,
BUT on Debian/Hurd , i am able to read data , it seem to read the content of the directory inode .

What do you think ? 

If this is not a bug , where i can find more information on it ?

If this is a bug where do i need to report ?

If this mailing-list is not the right media for speaking about this , where i can find more help ?

Thanks 
-- 
Erwan MAS