Hiredis BLPOP in a thread

poptest.c

#include <stdio.h>
#include <string.h>
#include <pthread.h>
#include <hiredis/hiredis.h>

void *popWorker(void *context) {
    const char *channel = (char*)context;
    struct timeval tv = {1, 0};
    redisContext *c;
    redisReply *r;

    c = redisConnectWithTimeout("localhost", 6379, tv);
    if (!c || c->err) {
        fprintf(stderr, "Can't connect to redis\n");
        return NULL;
    }

    while (1) {
        r = redisCommand(c, "BLPOP %s 0", channel);
        if (r == NULL || c->err) {
            fprintf(stderr, "Error reading from list\n");
            return NULL;
        }

        if (r->type != REDIS_REPLY_ARRAY || r->elements < 2) {
            fprintf(stderr, "Invalid BLPOP reply from Redis\n");
            return NULL;
        }

        if (!strcmp(r->element[1]->str, "exit")) {
            printf("Received 'exit' message, shutting down...\n");
            return NULL;
        }

        printf("Redis: %s => %s\n", r->element[0]->str, r->element[1]->str);
        freeReplyObject(r);
    }
}


int main(void) {
    pthread_t worker;
    const char *channel = "testlist";

    /* Create our worker */
    if (pthread_create(&worker, NULL, popWorker, (void*)channel) != 0) {
        fprintf(stderr, "Can't start thread\n");
        return 1;
    }

    /* Wait for it to finish */
    pthread_join(worker, NULL);

    printf("All done...\n");
}