compiling fiddle.c
In file included from fiddle.c:1:0:
./fiddle.h:18:17: fatal error: ffi.h: No such file or directory
compilation terminated.
make[2]: *** [fiddle.o] Error 1
make[2]: Leaving directory `/home/dagnachew/.rvm/src/ruby-1.9.3-p194/ext/fiddle'
make[1]: *** [ext/fiddle/all] Error 2
make[1]: Leaving directory `/home/dagnachew/.rvm/src/ruby-1.9.3-p194'
make: *** [build-ext] Error 2