find . -path "*/trunk/src/*.h"
find . -path "*/trunk/src/*.cpp"

find . -path '*/trunk/src/*.h' -o -path '*/trunk/src/*.cpp'

find . -path '*/trunk/src/*' ( -name '*.h' -o -name '*.cpp' )

find . ( -path '*/trunk/src/*.h' -o -path '*/trunk/src/*.cpp' ) -exec grep PATTERN {} +

find . -path '*/trunk/src/*' ( -name '*.h' -o -name '*.cpp' ) -exec grep PATTERN {} +

shopt -s globstar extglob

grep PATTERN **/trunk/src/**/*.@(h|cpp)

grep PATTERN **/trunk/src/**/*.(h|cpp)

grep -R --include='*.cpp' --include='*.h' PATTERN **/trunk/src