Returns the remaining time to live of a key that has a timeout. This introspection capability allows a Redis client to check how many seconds a given key will continue to be part of the dataset.
In Redis 2.6 or older the command returns -1 if the key does not exist or if the key exist but has no associated expire.
Starting with Redis 2.8 the return value in case of error changed:
- The command returns
-2if the key does not exist. - The command returns
-1if the key exists but has no associated expire.
See also the PTTL command that returns the same information with milliseconds resolution (Only available in Redis 2.6 or greater).
@return
@integer-reply: TTL in seconds, or a negative value in order to signal an error (see the description above).
@examples
SET mykey "Hello"
EXPIRE mykey 10
TTL mykey