svn st | grep ^? | xargs svn add
or removing unwanted files from subversion:
find . -name "expr" | xargs svn rm
But for my task I needed to use cp operation on a list of files. A little frustrated with myself for not knowing this by now I decided to google and finally learn. So, here's what I learned tonight about xargs. It's very easy to execute a command and use the result of that command anywhere in the expression executed via xargs.
find src/ -name "*.java" | xargs -I {} cp {} src/rhg/crawler/
