Subversion documentation can sometimes seem quite scant. If you want to use command line svn to update a series of folders, automatically merging each file that needs to be, use

svn update --non-interactive

This will keep away the prompts: "Conflict discovered in "

Instead some of the updated files might/will get some of the markings as below but your compiler should make that obvious later
<<<<<<< .mine
>>>>>>> .r191289