I didn't put that much thought into the process, though I really despise routines that alter their parameters needlessly. (And in this case it really seems that way) The XS code could potentially be cleaned up some, with the length getting subsumed into the length of the resulting SV string, which'd be the better way to do it, I expect. Checking the want status is also reasonable, and having different returns based on it. Either of those (multiple returns, or want-based returns) are 'better' than altering the input, or at least so go my preferences.

Still, I very much mistrust code that uses returned buffers from libraries. While it's OK in some cases, I've found myself burned often enough with library buffer reuse or freeing at odd times that I much prefer making a copy of the data. It's very rarely large enough to be a performance issue, and those cases can be handled specially. It's generally better, especially for folks who aren't used to writing XS code, to make the copy and optimize it away later, since that gets them the safe case by default.


In reply to Re: Re^2: Perl XS: garbage-collecting my malloc'd buffer (perlish?) by Elian
in thread Perl XS: garbage-collecting my malloc'd buffer by edan

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