getLibexecDir = catchIO (getEnv "isbn_verifier_libexecdir") (\_ -> return libexecdir)
getLibexecDir = catchIO (getEnv "isbn_verifier_libexecdir") (\_ -> return libexecdir)
getLibexecDir = catchIO (getEnv "isbn_verifier_libexecdir") (\_ -> return libexecdir)