Is 'show_c_source()' broken?

Question

Been trying to use show_c_source() from Hadley Wickhams pryr package, and every time I get the following error message:

Error in file(con, "r") : cannot open the connection

Even the examples provided in the function documentation do not work:

 > example("show_c_source")

 shw_c_> ## No test: 
 shw_c_> show_c_source(.Internal(mean(x)))
 Error in file(con, "r") : cannot open the connection

I'm running this on a 10.11.3 Mac OSX, R 3.2.4