ssh_add_identity_constrained
int ssh_add_identity_constrained(int sock, struct sshkey *key,
(r = ssh_add_identity_constrained(agent_fd, private, comment,
if ((r = ssh_add_identity_constrained(agent_fd, private, comment,
if ((r = ssh_add_identity_constrained(agent_fd, key, "",
if ((r = ssh_add_identity_constrained(auth_sock, private,
ssh_add_identity_constrained(auth, key, comment, 0, 0, 0, NULL, NULL, 0)