Consider using CLI11 in place of getopt

Created by: matthew-d-jones

The syntax of CLI11 looks much nicer than getopt. It also has the advantage of being cross-platform; getopt is POSIX-only. The library is header-only and bincrafters have released a conan package.

https://github.com/CLIUtils/CLI11 https://bintray.com/bincrafters/public-conan/cli11%3Abincrafters