[PATCH] libio: Avoid dup already opened file descriptor [BZ#21393]

[Adhemerval Zanella]

On 22/05/2017 17:21, Siddhesh Poyarekar wrote:
> On Tuesday 23 May 2017 01:48 AM, Adhemerval Zanella wrote:
>> Alright, I will change it (I based this doc from freopen(3) btw).
> 
> Oh, which version?  I was going to suggest writing a man page patch as
> well :)
> 
> Siddhesh
> 

Release 4.04 and I in fact it came from dup3(2) (my mistake):

       EBUSY  (Linux only) This may be returned by dup2() or dup3() during a 
race condition with open(2) and dup().