On Mon, Dec 09, 2024 at 11:33:02PM +0100, Andreas Schwab wrote:
> On Dez 09 2024, Mike Jonkmans wrote:
>
> > But the PIPESTATUS refers to the 'false' pipeline:
> > $ if false; then :; fi; echo ${PIPESTATUS[*]}
> > 1
>
> $ if false; then :; fi | true; echo ${PIPESTATUS[*]}
> 0 0
>
> Why is that not `1 0'? After all, the last executed commands as part of
> the pipeline (by your reasoning) are `false' and `true'.
My reasoning:
With 'if false... fi | true' there are two pipelines:
1) false
2) (compound command) if | true
The second pipeline, is the last, and that is where PIPESTATUS refers to.
Both parts of the second pipeline have 0 as status.
Confusing is that one could perceive more pipelines.
One for the compoud command (if) and one for the simple command (true).
[ Note that the simple command 'false' is considered a pipeline. ]
Then 'true' might be the "most-recently-executed foreground pipeline".
(term used in `man bash' explaining PIPESTATUS).
Disregarding the 'foreground' aspect.
The "most-recently-executed pipeline" might need some more clarification:
- What is considered a pipeline?
- How to determine 'most-recently-executed'?
--
Regards, Mike Jonkmans
