Code review comment for lp:~raof/mir/from-the-neglected-branches-files

(1) The third constructor parameter is unnecessary if you're not going to provide any more rich information. You'd get just as useful a string by omitting it and letting the system get an error message (like strerror?):
19 + boost::enable_error_info(std::system_error(errno,
20 + std::system_category(),
21 + "Failed to create pipe")));

(2) Unused #include?... tests/mir_test_framework/udev_environment.cpp