On 15 Jul 2014, at 00:32, Jens Alfke <j...@mooseyard.com> wrote: > > On Jul 14, 2014, at 1:07 PM, Carl Hoefs <newsli...@autonomy.caltech.edu> > wrote: > >> modifiableData = [ NSMutableData dataWithData: [ external call that gives >> me an NSData ] ]; > > It’s shorter and more idiomatic to just say > modifiableData = [external mutableCopy]; > (plus an autorelease if you’re not using ARC) > >> Will get it working first, and if there's a performance panic, perhaps >> something can be done (but I extremely doubt it). > > > Well, the most optimal thing to do would be to create an empty NSMutableData > of the correct size, then use memcpy to copy in the correct pieces from the > original NSData and whatever other sources there are. That will save you some > unnecessary copies and possibly realloc calls.
Another possibility is to use dispatch_data. Rather than copy bytes around to assemble them into a contiguous buffer, your use case might be just as well suited to dispatch_data’s approach of tying together various non-contiguous buffers. _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
