Re: passfd on more platforms

[Bruno Haible]

Eric Blake asked:
> >   - to rewrite the test to use the 'execute' module instead of fork().
> 
> Why do we even need a child process?  Can't we test passing of an fd
> between two threads of the same process?

1) Because the typical use-case is passing file descriptors between different
   processes.
2) Because passing file descriptors implies a conversion step (that happens in
   the kernel), and a unit test that only uses two threads doesn't exercise
   this essential part of the functionality: If the conversion step was
   missing, the test wouldn't notice.

Bruno