func (s *RepositoriesService) ListForks(owner, repo string, opt *RepositoryListForksOptions) ([]Repository, *Response, error) {
	u := fmt.Sprintf("repos/%v/%v/forks", owner, repo)
	u, err := addOptions(u, opt)
	if err != nil {
		return nil, nil, err
	}
	req, err := s.client.NewRequest("GET", u, nil)
	if err != nil {
		return nil, nil, err
	}
	repos := new([]Repository)
	resp, err := s.client.Do(req, repos)
	if err != nil {
		return nil, resp, err
	}
	return *repos, resp, err
}
ListForks lists the forks of the specified repository.

GitHub API docs: http://developer.github.com/v3/repos/forks/#list-forks
package github
import "fmt"
type RepositoryListForksOptions struct {
	Sort string `url:"sort,omitempty"`
	ListOptions
}