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.

As I explained in the other reply, returning the count does not work 
beyond 255 jobs, so as long as this is clear to the user, one or the 
other works. If GNU parallel returns the count of errors, the user will 
have to interpret the exit code differently if the job count exceeds 255.

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

I have no idea about this scenario.

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

The same answer as above. :-)

Thanks,
Martin