Description
Returns the time to live left for a given key, in milliseconds. If the key doesn't exist, FALSE is returned. ttl in seconds returns a time .
取得一个KEY已经存在的时间,单位是毫秒。如果这个KEY不存在，则返回FLASE。TTL使用毫秒为单位。
Parameters
Key: key
Return value
Long, the time left to live in milliseconds.
Example
$redis->pttl('key');