[Twisted-Python] getProcessOutput ok to use in a DeferredList?

Stuart Hungerford stuart.hungerford at anu.edu.au
Mon May 26 21:42:49 EDT 2003


 > [...]
 >I'm going to guess what your problem might be, based on a problem I once
 >had.  :)
 >
 >If you have multiple Deferreds, some "depend" on others, DeferredList's
 >default behaviour isn't what you want.  By "depend" I mean if Deferred A
 >fails (and so fires its errback, not callback), then Deferred B will never
 >be called, i.e. B depends on A.  (This is not official terminology! :).
 >
 >In that case, you probably want to use the fireOnOneErrback flag of
 >DeferredList.  This changes the behaviour of DeferredList so that it will
 >fire its callbacks as soon as either:
 >    - All its Deferreds have fired their callbacks, or
 >    - any of its Deferreds have fired an errback.

    Aha! A brilliant piece of remote empathetic debugging ;-)  The lack of
    an errback was masking an error from the Deferreds.  Many thanks.



Cheers,

Stu

--
:: Stuart Hungerford (stuart.hungerford at anu.edu.au)
:: ANU Internet Futures Group





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