When you render an animation in Blender 3D on a Mac it is immediately saved into a folder called /tmp/. Unfortunately this folder is hidden so you can’t go and get your render.
To open it (and get your files) simply do the following: Press SHIFT+CMD+G and type /tmp/
Using Blender 2.79rc on a Mac with Sierra OS. Since upgrading to Blender 2.79rc I have found, when rendering a video as individual frames (.png), that the location I specified to which the frames should be saved is ignored and have instead been saved to Blender’s /tmp/ folder. Trying to locate this folder and the files files therein has caused me a problem but thanks to your post this has now been solved. Just go to finder, do the shift+cmd+G key combo and then move all your files somewhere sensible. Phew! Thought I’d lost many hours of rendering.
Thanks a ton!