(PECL ssh2 >= 0.9.0)
ssh2_sftp_unlink — Delete a file
$sftp, string $filename): boolDeletes a file on the remote filesystem.
成功时返回 true， 或者在失败时返回 false。
示例 #1 Deleting a file
<?php
$connection = ssh2_connect('shell.example.com', 22);
ssh2_auth_password($connection, 'username', 'password');
$sftp = ssh2_sftp($connection);
ssh2_sftp_unlink($sftp, '/home/username/stale_file');
?>