原文链接：http://lontoken.com/memcached_install_and_libmemcached_uses.html

memcached安装和libmemcached的使用

环境和版本

操作系统：Ubuntu14.04 32bit
libevent版本: 2.0.21
memdatach版本: v1.4.21

libevent安装

#wget http://github.com/downloads/libevent/libevent/libevent-2.0.21-stable.tar.gz
#tar -xvzf libevent-2.0.21-stable.tar.gz
#cd libevent-2.0.21-stable
#./configure -prefix=/usr
#make
#make install

查看是否安装成功:

#ls /usr/lib/ | grep  libevent

memcached安装

#wget wget http://www.memcached.org/files/memcached-1.4.21.tar.gz
#tar -xvzf memcached-1.4.21.tar.gz
#cd memcached-1.4.21
#./configure -with-libevent=/usr
#make
#make install

查看是否安装成功:

#ll /usr/local/bin

memcached启动

#/usr/local/bin/memcached -d -u root -m 512 127.0.0.1 -p 11211

查看侦听端口和进程信息：

#netstat -a |grep 11211
#ps -ef | grep memcached

测试memcached

连接memcached最简单的方法是通过telnet。

#telnet 127.0.0.1 11211

查看memcached的状态(telnet下执行):

stats

键值简单的设置、查看和删除(telnet下执行):

set user_id 0 0 5
12345
get user_id
delete user_id
get user_id

PS:退出telnet，可以键入alt+] q

libmemcached安装

#wget https://launchpad.net/libmemcached/1.0/1.0.18/+download/libmemcached-1.0.18.tar.gz
#tar -xvzf libmemcached-1.0.18.tar.gz
#cd libmemcached-1.0.18
#./configure
#make
#make install

查看libmemcached是否安装成功:

#ls /usr/local/lib | grep libmemcached

使用C++通过libmemcached连接memcached#

C++源文件 libmemcachedtest.cpp

 1 #include <iostream>
 2 #include <string>
 3 #include <libmemcached/memcached.h>
 4
 5 using namespace std;
 6
 7 int main(int argc, char *argv[])
 8 {
 9     //connect server
10     cout << "test start" << endl;
11     memcached_st *memc;
12     memcached_return rc;
13     memcached_server_st *server;
14     uint32_t  flags;
15
16     memc = memcached_create(NULL);
17     cout << "append start" << endl;
18     server = memcached_server_list_append(NULL, "localhost", 11211, &rc);
19     if(rc != MEMCACHED_SUCCESS){
20         cout << "memcached_server_list_append failed. rc=" << rc << endl;
21         return -1;
22     }
23
24     rc = memcached_server_push(memc, server);
25     if(rc != MEMCACHED_SUCCESS){
26         cout << "memcached_server_push failed. rc=" << rc << endl;
27         memcached_server_free(server);
28         return -2;
29     };
30
31     memcached_server_list_free(server);
32
33     string key = "key";
34     string value = "value";
35     size_t value_length = value.length();
36     size_t key_length = key.length();
37
38     //Save data
39     cout << "save data" << endl;
40     rc = memcached_set(memc, key.c_str(), key_length, value.c_str(), value_length, 0, flags);
41     if(rc == MEMCACHED_SUCCESS){
42         cout << "save data sucessful, key=" << key << ",value=" << value <<endl;
43     }else{
44         cout << "save data faild, rc=" << rc <<endl;
45     }
46
47     //get data
48     cout << "get data" << endl;
49     char* result = memcached_get(memc, key.c_str(), key_length, &value_length, &flags, &rc);
50     if(rc == MEMCACHED_SUCCESS){
51         cout << "get value sucessful, result=" << result <<endl;
52     }else{
53         cout << "get value faild, rc=" << rc <<endl;
54     }
55
56     //delete data
57     cout << "delete data" << endl;
58     rc = memcached_delete(memc, key.c_str(), key_length, 0);
59     if(rc == MEMCACHED_SUCCESS){
60         cout << "delete key sucessful. key=" << key << endl;
61     }else{
62         cout << "delete key faild, rc=" << rc <<endl;
63     }
64
65     //free
66     memcached_free(memc);
67     cout << "test end." << endl;
68     return 0;
69 }

编译前需要设置LD_LIBRARY_PATH环境变更，以使libmemcached能被找到。

$export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib/

编译并执行：

$g++ -std=c++11 -o libmemcachedtest libmemcachedtest.cpp -lmemcached
$./libmemcachedtest

如果一切顺利，输出如下：

test start
append start
save data
save data sucessful, key=key,value=value
get data
get value sucessful, result=value
delete data
delete key sucessful. key=key
test end.