Re: Redirect a specific file descriptor to a pipe?

Re: Redirect a specific file descriptor to a pipe?

[Stephane Chazelas]

2017-03-10 18:24:30 -0800, Bart Schaefer:
> On Mar 10,  4:32pm, Nathan Dorfman wrote:
> }
> } I still think it might be useful to be able to pipe any fd, not just
> } stdout, but I don't know if I can contrive a great example.
> 
> It depends on what your intentions are.  The definition of a pipeline
> in shell syntax is that the standard output of the left side connects
> to the standard input of the right side.  So if you want to use a pipe,
> you have to make the right thing *be* stdout, regardless of which other
> descriptor it might have started out to be.
[...]

For information, the rc shell allows piping any fd, not just
stdout on the left command to stdin of the right command.

cmd1 |[3=4] cmd2

Would make a pipe in between fd 3 of cmd1 and fd 4 of cmd2


yash has a pipeline redirection operator (shaped like ksh's
process substitution operator).

cmd1 3>(cmd2)

Runs cmd1 with fd 3 to a pipe to fd 0 of cmd2.

yash doesn't wait for cmd2 there though.

-- 
Stephane