compile
$ make gen
$ make
run
$ ./server
$ ./client
introspect and call using gdbus command line
$ gdbus introspect -e -d com.fatminmin -o /com/fatminmin/GDBUS
$ gdbus call -e -d com.fatminmin -o /com/fatminmin/GDBUS -m com.fatminmin.GDBUS.HelloWorld [your name]
gdbus-codegen call
$ gdbus-codegen --generate-c-code minminbus \
--c-namespace MinMinBus \
--interface-prefix com.fatminmin. \
com.fatminmin.GDBUS.xml