code: func registerFlags(c *cli.Config, f *flag.FlagSet) {
  	f.StringVar(&c.CertFile, "cert", "", "Client certificate that contains the public key")
  	f.StringVar(&c.KeyFile, "key", "", "private key for the certificate")
  	f.StringVar(&c.CABundleFile, "ca-bundle", "", "path to root certificate store")
  	f.StringVar(&c.IntBundleFile, "int-bundle", "", "path to intermediate certificate store")
  	f.StringVar(&c.Flavor, "flavor", "ubiquitous", "Bundle Flavor: ubiquitous, optimal and force.")
  	f.StringVar(&c.IntDir, "int-dir", "", "specify intermediates directory")
  	f.StringVar(&c.Metadata, "metadata", "", "Metadata file for root certificate presence. The content of the file is a json dictionary (k,v): each key k is SHA-1 digest of a root certificate while value v is a list of key store filenames.")
  	f.StringVar(&c.Domain, "domain", "", "remote server domain name")
  	f.StringVar(&c.IP, "ip", "", "remote server ip")
  	f.StringVar(&c.Password, "password", "0", "Password for accessing PKCS #12 data passed to bundler")
  }
docs: // registerFlags defines all cfssl command flags and associates their values with variables.