I think, the best way will be:
- Trim Entities
- Check circle
- CTRL + A
It's working good for me!
It doesn't work for me. It is either pulling all sketches the into the closed contour, or it's only keeping the lines that are coinident with the closed contour
It should work with trim away outside.
Select trim away outside mode, then select circle and press ctrl-A.
Unfortunately after a quick check i found that this will also extend other entities to the circle boundary.