Re: Which exit code should --halt give?

[Martin d'Anjou]

On 15-05-02 06:37 AM, Ole Tange wrote:
> On Sat, May 2, 2015 at 12:26 PM, Ole Tange <ole@tange.dk> wrote:
>
> > --halt soon,success=1 == --halt -1
> It will be useful to distinguish between halting because a job
> succeeded (e.g. a solution was found) or because there are no more
> jobs (e.g. no solution was found). So I think these should give
> different exit codes:
>
>    parallel --halt soon,success=1 exit ::: 0 1; echo $?

This should return 0 because the expectation (at least one success) was met.

>    parallel --halt soon,success=1 exit ::: 1 1; echo $?

This should return 1 because the expectation was not met.

> But I am less sure what the exit code should represent if there are no
> successes. It could be the number of failing jobs or the exit code of
> the first/last failing job if any.

The number of failing jobs has to be interpreted by the user when the 
number of jobs exceeds 255. GNU Parallel should not return 0 in this 
case when there is an error.

> And what should then be the exit
> code if no jobs were run? (e.g. parallel -r exit ::: '')

I do not know.

> > --halt now,success=1 == --halt -2
> The same argument as above.

IMO this should return 0 when at least one job succeeds. The user has 
set that expectation.

Martin