redis - Hiredis waiting for message -

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i using hiredis c library connect redis server. not able figure out how wait new messages after subscribing new message.

my code like:

signal(sigpipe, sig_ign );   struct event_base *base = event_base_new();    redisasynccontext *c = redisasyncconnect("127.0.0.1", 6379);   if (c->err) {     /* let *c leak now... */     printf("error: %s\n", c->errstr);     return 1;   }    redislibeventattach(c, base);   redisasyncsetconnectcallback(c, connectcallback);   redisasyncsetdisconnectcallback(c, disconnectcallback);   redisasynccommand(c, null, null, "set key %b", argv[argc - 1],                     strlen(argv[argc - 1]));   redisasynccommand(c, getcallback, (char*) "end-1", "get key");   redisasynccommand(c, getcallback, (char*) "end-1", "subscribe foo");

now how tell hiredis wait message on channel ?

you not have tell hiredis need wait on channel: event loop wait on redis connection has been registered.

here complete example:

#include <stdio.h> #include <stdlib.h> #include <string.h> #include <signal.h> #include "hiredis.h" #include "async.h" #include "adapters/libevent.h"  void subcallback(redisasynccontext *c, void *r, void *priv) {     redisreply *reply = r;     if (reply == null) return;     if ( reply->type == redis_reply_array && reply->elements == 3 ) {         if ( strcmp( reply->element[0]->str, "subscribe" ) != 0 ) {             printf( "received[%s] channel %s: %s\n",                     (char*)priv,                     reply->element[1]->str,                     reply->element[2]->str );         }     } }  void connectcallback(const redisasynccontext *c, int status) {     if (status != redis_ok) {         printf("error: %s\n", c->errstr);         return;     }     printf("connected...\n"); }  void disconnectcallback(const redisasynccontext *c, int status) {     if (status != redis_ok) {         printf("error: %s\n", c->errstr);         return;     }     printf("disconnected...\n"); }  int main (int argc, char **argv) {     signal(sigpipe, sig_ign);     struct event_base *base = event_base_new();      redisasynccontext *c = redisasyncconnect("127.0.0.1", 6379);     if (c->err) {         /* let *c leak now... */         printf("error: %s\n", c->errstr);         return 1;     }      redislibeventattach(c,base);     redisasyncsetconnectcallback(c,connectcallback);     redisasyncsetdisconnectcallback(c,disconnectcallback);     redisasynccommand(c, subcallback, (char*) "sub", "subscribe foo");      event_base_dispatch(base);     return 0; }

you can test use following command publish something:

redis-cli publish foo

the event_base_dispatch function 1 launches event loop, , makes wait on redis subscription.


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