标签：数据 c++ 点数据 exit develop strlen span size null
参考官方文档：http://docs.libmemcached.org/index.html
根据菜鸟教程上介绍，c++实现了连接memcached的客户端。
通过apt-cache search，查到到了需要安装的库
root@iZwz9aujzgp9b5o38x29akZ:~# apt-cache search memcached | grep C++ libmemcached-dev - C and C++ client library to the memcached server (development files) libmemcached11 - C and C++ client library to the memcached server
于是分别安装了libmemcached-dev与libmemcached11
root@iZwz9aujzgp9b5o38x29akZ:~# apt-get install libmemcached11 .....//略 root@iZwz9aujzgp9b5o38x29akZ:~# apt-get install libmemcached-dev .....//略
然后找到头文件
root@iZwz9aujzgp9b5o38x29akZ:~# cd /usr/include/libmemcached/ root@iZwz9aujzgp9b5o38x29akZ:/usr/include/libmemcached# ll total 20 drwxr-xr-x 2 root root 4096 Jan 19 19:16 ./ drwxr-xr-x 40 root root 4096 Jan 19 19:15 ../ -rw-r--r-- 1 root root 1713 Jan 18 2019 memcached.h -rw-r--r-- 1 root root 1717 Jan 18 2019 memcached.hpp -rw-r--r-- 1 root root 1714 Jan 18 2019 util.h
与libmemcached官方文档相符
接下来就是要写个测试程序，连上memcached
根据官方文档的资源，写了如下测试程序
vim connect_to_memcached.cpp
1 #include <iostream> 2 3 #include <string.h> 4 #include <libmemcached/memcached.h> 5 6 using namespace std; 7 int main() 8 { 9 const char * config_string = "--SERVER=127.0.0.1"; 10 memcached_st * memc = NULL; 11 cout << static_cast<const void *>(memc) << endl; 12 memc = memcached(config_string, strlen(config_string)); 13 cout << static_cast<const void *>(memc) << endl; 14 memcached_free(memc); 15 cout << static_cast<const void *>(memc) << endl; 16 return 0; 17 }
编译
g++ connect_to_memcached.cpp -o connect_to_memcached.exe /tmp/ccf2s5UM.o: In function `main‘: connect_to_memcached.cpp:(.text+0x2d): undefined reference to `memcached‘ connect_to_memcached.cpp:(.text+0x3d): undefined reference to `memcached_free‘ collect2: error: ld returned 1 exit status
这里报错了，是因为没有链接其动态库，最终链接失败
g++ connect_to_memcached.cpp -lmemcached -o connect_to_memcached.exe
编译成功。执行./connect_to_memcached.exe
root@iZwz9aujzgp9b5o38x29akZ:~/memcached_cpp# ./connect_to_memcached.exe 0 0x557ca3ff3280 0x557ca3ff3280
说明memcached()给其分配了空间。为了证明连接上了，需要再从memcache里取点数据看看
1 #include <iostream> 2 3 #include <string.h> 4 #include <libmemcached/memcached.h> 5 6 using namespace std; 7 8 int main() 9 { 10 const char * config_string = "--SERVER=127.0.0.1"; 11 memcached_st * memc = memcached(config_string, strlen(config_string)); 12 memcached_return_t ret; 13 const char * key = "name"; 14 size_t value_len; 15 uint32_t flags; 16 char * value = memcached_get(memc, key, strlen(key), &value_len, &flags, &ret); 17 cout << "key:" << key << endl; 18 cout << "ret:" << ret << endl; 19 20 if(memcached_success(ret)) 21 { 22 cout << "value:" << value << endl; 23 cout << "value_len:" << value_len << endl; 24 cout << "flags:" << flags << endl; 25 } 26 else 27 { 28 cout << "memcached_get fail" << endl; 29 } 30 31 memcached_free(memc); 32 return 0; 33 }
root@iZwz9aujzgp9b5o38x29akZ:~/memcached_cpp# g++ connect_to_memcached.cpp -lmemcached -o connect_to_memcached.exe root@iZwz9aujzgp9b5o38x29akZ:~/memcached_cpp# ./connect_to_memcached.exe key:name ret:0 value:ccx value_len:3 flags:0
标签：数据 c++ 点数据 exit develop strlen span size null
原文地址：https://www.cnblogs.com/chinxi/p/12215588.html
