#include <stdio.h>#include <stdlib.h>#include <stddef.h>#include <stdarg.h>#include <string.h>#include <assert.h>#include <hiredis.h>void doTest(){  int timeout = 10000;  struct timeval tv;  tv.tv_sec = timeout / 1000;  tv.tv_usec = timeout * 1000;  //以帶有超時(shí)的方式鏈接Redis服務(wù)器，同時(shí)獲取與Redis連接的上下文對(duì)象。  //該對(duì)象將用于其后所有與Redis操作的函數(shù)。  redisContext* c = redisConnectWithTimeout("192.168.149.137",6379,tv);  if (c->err) {    redisFree(c);    return;  }  const char* command1 = "set stest1 value1";  redisReply* r = (redisReply*)redisCommand(c,command1);  //需要注意的是，如果返回的對(duì)象是NULL，則表示客戶端和服務(wù)器之間出現(xiàn)嚴(yán)重錯(cuò)誤，必須重新鏈接。  //這里只是舉例說(shuō)明，簡(jiǎn)便起見(jiàn)，后面的命令就不再做這樣的判斷了。  if (NULL == r) {    redisFree(c);    return;  }  //不同的Redis命令返回的數(shù)據(jù)類型不同，在獲取之前需要先判斷它的實(shí)際類型。  //至于各種命令的返回值信息，可以參考Redis的官方文檔，或者查看該系列博客的前幾篇  //有關(guān)Redis各種數(shù)據(jù)類型的博客。:)  //字符串類型的set命令的返回值的類型是REDIS_REPLY_STATUS，然后只有當(dāng)返回信息是"OK"  //時(shí)，才表示該命令執(zhí)行成功。后面的例子以此類推，就不再過(guò)多贅述了。  if (!(r->type == REDIS_REPLY_STATUS && strcasecmp(r->str,"OK") == 0)) {    printf("Failed to execute command[%s]./n",command1);    freeReplyObject(r);    redisFree(c);    return;  }  //由于后面重復(fù)使用該變量，所以需要提前釋放，否則內(nèi)存泄漏。  freeReplyObject(r);  printf("Succeed to execute command[%s]./n",command1);  const char* command2 = "strlen stest1";  r = (redisReply*)redisCommand(c,command2);  if (r->type != REDIS_REPLY_INTEGER) {    printf("Failed to execute command[%s]./n",command2);    freeReplyObject(r);    redisFree(c);    return;  }  int length = r->integer;  freeReplyObject(r);  printf("The length of 'stest1' is %d./n",length);  printf("Succeed to execute command[%s]./n",command2);  const char* command3 = "get stest1";  r = (redisReply*)redisCommand(c,command3);  if (r->type != REDIS_REPLY_STRING) {    printf("Failed to execute command[%s]./n",command3);    freeReplyObject(r);    redisFree(c);    return;  }  printf("The value of 'stest1' is %s./n",r->str);  freeReplyObject(r);  printf("Succeed to execute command[%s]./n",command3);  const char* command4 = "get stest2";  r = (redisReply*)redisCommand(c,command4);  //這里需要先說(shuō)明一下，由于stest2鍵并不存在，因此Redis會(huì)返回空結(jié)果，這里只是為了演示。  if (r->type != REDIS_REPLY_NIL) {    printf("Failed to execute command[%s]./n",command4);    freeReplyObject(r);    redisFree(c);    return;  }  freeReplyObject(r);  printf("Succeed to execute command[%s]./n",command4);  const char* command5 = "mget stest1 stest2";  r = (redisReply*)redisCommand(c,command5);  //不論stest2存在與否，Redis都會(huì)給出結(jié)果，只是第二個(gè)值為nil。  //由于有多個(gè)值返回，因?yàn)榉祷貞?yīng)答的類型是數(shù)組類型。  if (r->type != REDIS_REPLY_ARRAY) {    printf("Failed to execute command[%s]./n",command5);    freeReplyObject(r);    redisFree(c);    //r->elements表示子元素的數(shù)量，不管請(qǐng)求的key是否存在，該值都等于請(qǐng)求是鍵的數(shù)量。    assert(2 == r->elements);    return;  }  for (int i = 0; i < r->elements; ++i) {    redisReply* childReply = r->element[i];    //之前已經(jīng)介紹過(guò)，get命令返回的數(shù)據(jù)類型是string。    //對(duì)于不存在key的返回值，其類型為REDIS_REPLY_NIL。    if (childReply->type == REDIS_REPLY_STRING)      printf("The value is %s./n",childReply->str);  }  //對(duì)于每一個(gè)子應(yīng)答，無(wú)需使用者單獨(dú)釋放，只需釋放最外部的redisReply即可。  freeReplyObject(r);  printf("Succeed to execute command[%s]./n",command5);  printf("Begin to test pipeline./n");  //該命令只是將待發(fā)送的命令寫入到上下文對(duì)象的輸出緩沖區(qū)中，直到調(diào)用后面的  //redisGetReply命令才會(huì)批量將緩沖區(qū)中的命令寫出到Redis服務(wù)器。這樣可以  //有效的減少客戶端與服務(wù)器之間的同步等候時(shí)間，以及網(wǎng)絡(luò)IO引起的延遲。  //至于管線的具體性能優(yōu)勢(shì)，可以考慮該系列博客中的管線主題。  if (REDIS_OK != redisAppendCommand(c,command1)    || REDIS_OK != redisAppendCommand(c,command2)    || REDIS_OK != redisAppendCommand(c,command3)    || REDIS_OK != redisAppendCommand(c,command4)    || REDIS_OK != redisAppendCommand(c,command5)) {    redisFree(c);    return;  }  redisReply* reply = NULL;  //對(duì)pipeline返回結(jié)果的處理方式，和前面代碼的處理方式完全一直，這里就不再重復(fù)給出了。  if (REDIS_OK != redisGetReply(c,(void**)&reply)) {    printf("Failed to execute command[%s] with Pipeline./n",command1);    freeReplyObject(reply);    redisFree(c);  }  freeReplyObject(reply);  printf("Succeed to execute command[%s] with Pipeline./n",command1);  if (REDIS_OK != redisGetReply(c,(void**)&reply)) {    printf("Failed to execute command[%s] with Pipeline./n",command2);    freeReplyObject(reply);    redisFree(c);  }  freeReplyObject(reply);  printf("Succeed to execute command[%s] with Pipeline./n",command2);  if (REDIS_OK != redisGetReply(c,(void**)&reply)) {    printf("Failed to execute command[%s] with Pipeline./n",command3);    freeReplyObject(reply);    redisFree(c);  }  freeReplyObject(reply);  printf("Succeed to execute command[%s] with Pipeline./n",command3);  if (REDIS_OK != redisGetReply(c,(void**)&reply)) {    printf("Failed to execute command[%s] with Pipeline./n",command4);    freeReplyObject(reply);    redisFree(c);  }  freeReplyObject(reply);  printf("Succeed to execute command[%s] with Pipeline./n",command4);  if (REDIS_OK != redisGetReply(c,(void**)&reply)) {    printf("Failed to execute command[%s] with Pipeline./n",command5);    freeReplyObject(reply);    redisFree(c);  }  freeReplyObject(reply);  printf("Succeed to execute command[%s] with Pipeline./n",command5);  //由于所有通過(guò)pipeline提交的命令結(jié)果均已為返回，如果此時(shí)繼續(xù)調(diào)用redisGetReply，  //將會(huì)導(dǎo)致該函數(shù)阻塞并掛起當(dāng)前線程，直到有新的通過(guò)管線提交的命令結(jié)果返回。  //最后不要忘記在退出前釋放當(dāng)前連接的上下文對(duì)象。  redisFree(c);  return;}int main() {  doTest();  return 0;}//輸出結(jié)果如下：//Succeed to execute command[set stest1 value1].//The length of 'stest1' is 6.//Succeed to execute command[strlen stest1].//The value of 'stest1' is value1.//Succeed to execute command[get stest1].//Succeed to execute command[get stest2].//The value is value1.//Succeed to execute command[mget stest1 stest2].//Begin to test pipeline.//Succeed to execute command[set stest1 value1] with Pipeline.//Succeed to execute command[strlen stest1] with Pipeline.//Succeed to execute command[get stest1] with Pipeline.//Succeed to execute command[get stest2] with Pipeline.//Succeed to execute command[mget stest1 stest2] with Pipeline.