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Asked: 2026-05-30T13:45:41+00:00

Consider following example: #include <stdlib.h> #include <stdio.h> #include <errno.h> #include <hiredis/hiredis.h> int main(int argc,

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Consider following example:

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <hiredis/hiredis.h>

int main(int argc, char **argv) {
  redisContext *redis;
  redisReply *reply;

  redis = redisConnect("127.0.0.1", 6379);
  if(redis->err) {
    fprintf(stderr, "Connection error: %s\n", redis->errstr);
    exit(EXIT_FAILURE);
  }

  reply = redisCommand(redis, "SET %s %s", "foo", "bar");
  printf("SET %s %s: %s\n", "foo", "bar", reply->str);
  freeReplyObject(reply);

  reply = redisCommand(redis, "SET %s %s", "name", "value");
  printf("SET %s %s: %s\n", "name", "value", reply->str);
  freeReplyObject(reply);

  reply = redisCommand(redis, "MGET %s %s", "foo", "name");
  printf("MGET %s %s: %s\n", "foo", "name", reply->str);
  freeReplyObject(reply);

  exit(EXIT_SUCCESS);
}

The output is:

PING: PONG
SET foo bar: OK
GET foo: bar
SET name value: OK
MGET foo name: (null)

It’s about return from MGET. Can I get multi keys using hiredis?

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1 Answer

  1. Editorial Team

    A redisReply is a typed object (see the type field), and a multi-bulk reply has a specific type (REDIS_REPLY_ARRAY). The str field is not relevant in that case.

    From the hiredis documentation:

    The number of elements in the multi bulk reply is stored in reply->elements.
Every element in the multi bulk reply is a redisReply object as well
and can be accessed via reply->element[..index..].
Redis may reply with nested arrays but this is fully supported.

    So your code should be changed as follows:

    reply = redisCommand(redis, "MGET %s %s", "foo", "name" );
if ( reply->type == REDIS_REPLY_ERROR )
  printf( "Error: %s\n", reply->str );
else if ( reply->type != REDIS_REPLY_ARRAY )
  printf( "Unexpected type: %d\n", reply->type );
else 
{
  int i;
  for ( i=0; i<reply->elements; ++i )
    printf( "Result: %s\n", reply->element[i]->str );
}
freeReplyObject(reply);

    With this change, the output is now:

    SET foo bar: OK
SET name value: OK
Result: bar
Result: value

    Note: there is no need to free each individual element since freeReplyObject deletes the whole tree.

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