After registering the generated pub key to github, rerunning github-keygen will throw an error.
[user@fedora-23-dvm bin]$ ./github-keygen riqpe
Accounts: riqpe
riqpe: key is registered on GitHub.
No changes in ~/.ssh/known_hosts_github.
github-keygen: splice() offset past end of array at ./github-keygen line 697.
No changes in ~/.ssh/config.
[user@fedora-23-dvm bin]$
After registering the generated pub key to github, rerunning github-keygen will throw an error.