Re: implicit redirection of background within pipeline

[Chet Ramey]

On 1/10/16 12:54 PM, Piotr Grzybowski wrote:
> hey,
> 
>  I am quite sure it happens here (devel branch, at
> 6f82653c5ef09aeeeba4376a1c65ce86c3605c00):
> 
> execute_cmd.c +5115:
>    if ((cmdflags & CMD_STDIN_REDIR) &&
>   pipe_in == NO_PIPE &&
>   (stdin_redirects (redirects) == 0))
>      async_redirect_stdin ();
> 
>  but after reading the comments some 3.5k lines earlier I am not sure
> how to fix it; of course commenting out the if in
> execute_cmd.c:5112-5115 solves it, but who can tell what it breaks?

Posix requires this behavior:

"The standard input for an asynchronous list, before any explicit
redirections are performed, shall be considered to be assigned to a file
that has the same properties as /dev/null."

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