It is the blocking version because it blocks the connection when there are no members to pop from any of the given sorted sets. A member with the lowest score is popped from first sorted set that is non-empty, with the given keys being checked in the order that they are given.
timeout argument is interpreted as an integer value specifying the maximum
number of seconds to block. A timeout of zero can be used to block indefinitely.
Array reply: specifically:
nilmulti-bulk when no element could be popped and the timeout expired.
- A three-element multi-bulk with the first element being the name of the key where a member was popped, the second element being the score of the popped member, and the third element being the popped member itself.
redis> DEL zset1 zset2 (integer) 0 redis> ZADD zset1 0 a 1 b 2 c (integer) 3 redis> BZPOPMIN zset1 zset2 0 1) "zet1" 2) "0" 2) "a"