BITPOS - Upstash Documentation

Use BITPOS to find the position of the first bit set to 0 or 1 in a string. The whole value is searched unless <start> and <end> are given, and those are byte offsets by default or bit offsets when BIT is given. Both ends are inclusive and may be negative to count backwards from the end of the value. The reply is always an absolute bit position counted from the start of the string, or -1 when no matching bit is found. One edge case is worth remembering: when you look for a 0 in a string of all ones and give no explicit end, the reply is the position of the first bit past the end of the string, because the value is treated as if it were followed by an infinite run of zero bits. Bounding the search with an explicit range returns -1 in the same situation.

Syntax

BITPOS <key> <bit> [<start> [<end> [BYTE | BIT]]]

Arguments

Argument	Required	Repeatable	Description
`<key>`	Yes	No	Redis key targeted by the command.
`<bit>`	Yes	No	Bit value to look for: `0` or `1`.
`<start> [<end> [BYTE \| BIT]]`	No	No	Range to search. Offsets are byte-based unless `BIT` is given; negative offsets count from the end.

Response

The reply reports the result of the operation. Error replies have the same shape in RESP2 and RESP3 and are surfaced as exceptions by the SDKs below.

Protocol	Reply
RESP2	Integer: the position of the first matching bit, or `-1`
RESP3	Integer: the position of the first matching bit, or `-1`

Client libraries often decode bulk strings, maps, sets, and numeric strings into language-native values. The table describes the Redis wire reply.

Examples

TCP examples use the TLS REDIS_URL from the Upstash console. REST examples use UPSTASH_REDIS_REST_URL and UPSTASH_REDIS_REST_TOKEN.

Redis CLI

BITPOS my-key 1

@upstash/redis

import { Redis } from "@upstash/redis";

const redis = Redis.fromEnv();

await redis.bitpos("key", 1);

upstash_redis

from upstash_redis import Redis

redis = Redis.from_env()
result = redis.bitpos("my-key", 1)
print(result)

ioredis

import Redis from "ioredis";

const redis = new Redis(process.env.REDIS_URL!);
const result = await redis.bitpos("my-key", "1");
console.log(result);

node-redis

import { createClient } from "redis";

const client = await createClient({ url: process.env.REDIS_URL })
  .on("error", console.error)
  .connect();
const result = await client.bitPos("my-key", 1);
console.log(result);

redis-py

import os
import redis

client = redis.from_url(os.environ["REDIS_URL"])
result = client.bitpos("my-key", 1)
print(result)

go-redis

package main

import (
    "context"
    "fmt"
    "os"

    "github.com/redis/go-redis/v9"
)

func main() {
    opts, err := redis.ParseURL(os.Getenv("REDIS_URL"))
    if err != nil {
        panic(err)
    }
    client := redis.NewClient(opts)
    result, err := client.BitPos(context.Background(), "my-key", 1).Result()
    if err != nil {
        panic(err)
    }
    fmt.Println(result)
}

jedis

import java.net.URI;

import redis.clients.jedis.Jedis;

try (Jedis jedis = new Jedis(new URI(System.getenv("REDIS_URL")))) {
  Object result = jedis.bitpos("my-key", true);
  System.out.println(result);
}

redis-rs

fn main() -> redis::RedisResult<()> {
    let url = std::env::var("REDIS_URL").expect("REDIS_URL is not set");
    let client = redis::Client::open(url)?;
    let mut connection = client.get_connection()?;

    let mut command = redis::cmd("BITPOS");
    command.arg("my-key");
    command.arg("1");
    let result: redis::Value = command.query(&mut connection)?;
    println!("{result:?}");
    Ok(())
}

​Syntax

​Arguments

​Response

​Examples

Syntax

Arguments

Response

Examples