(PECL ssh2 >= 0.10)
ssh2_publickey_init — Initialize Publickey subsystem
Request the Publickey subsystem from an already connected SSH2 server.
The publickey subsystem allows an already connected and authenticated client to manage the list of authorized public keys stored on the target server in an implementation agnostic manner. If the remote server does not support the publickey subsystem, the ssh2_publickey_init() function will return FALSE.
Returns an SSH2 Publickey Subsystem resource for use with all other ssh2_publickey_*() methods, or FALSE on failure.
Note: 公钥系统用于管理服务器上的客户已经被认证的公钥。要用公钥认证方法在远程系统上认证，应该用 ssh2_auth_pubkey_file() 函数。