linux编程libevent安装

短命女 2022-12-02 04:12 368阅读 0赞

# linux编程libevent安装 #

下载libevent-2.1.8-stable.tar.gz，解压

tar -zxf libevent-2.1.8-stable.tar

或者

mkdir 321
    tar -zxf libevent-2.1.8-stable.tar -C ./321

进入目录

cd libevent-2.1.8-stable
    ls -la

这时，我们可以看到有一些是可以执行的。  
执行

./configure

生成makefile，执行make命令

make

# 测试 #

进入sample目录

cd sample

看一下`hello-world.c`文件，看到端口9995

#include <string.h>
    #include <errno.h>
    #include <stdio.h>
    #include <signal.h>
    #ifndef _WIN32
    #include <netinet/in.h>
    # ifdef _XOPEN_SOURCE_EXTENDED
    # include <arpa/inet.h>
    # endif
    #include <sys/socket.h>
    #endif
    
    #include <event2/bufferevent.h>
    #include <event2/buffer.h>
    #include <event2/listener.h>
    #include <event2/util.h>
    #include <event2/event.h>
    
    static const char MESSAGE[] = "Hello, World!\n";
    
    static const int PORT = 9995;
    
    static void listener_cb(struct evconnlistener *, evutil_socket_t,
        struct sockaddr *, int socklen, void *);
    static void conn_writecb(struct bufferevent *, void *);
    static void conn_eventcb(struct bufferevent *, short, void *);
    static void signal_cb(evutil_socket_t, short, void *);
    
    int
    main(int argc, char **argv)
    { 
            struct event_base *base;
            struct evconnlistener *listener;
            struct event *signal_event;
    
            struct sockaddr_in sin;

## 执行 ##

启动终端１，执行例子自带的hello-world程序。

$ ./hello-world

启动终端２，执行命令`nc 127.1 9995`，返回`Hello, World!`后立即断开，测试成功。

$ nc 127.1 9995
    Hello, World!

# 编译hello-world #

这里生成hello-world还是会报错，所以要安装一下。

$ gcc hello-world.c -o hello -levent

安装

$  sudo make install
     ...
     ...
    Libraries have been installed in:
       /usr/local/lib
    
    If you ever happen to want to link against installed libraries
    in a given directory, LIBDIR, you must either use libtool, and
    specify the full pathname of the library, or use the '-LLIBDIR'
    flag during linking and do at least one of the following:
       - add LIBDIR to the 'LD_LIBRARY_PATH' environment variable
         during execution
       - add LIBDIR to the 'LD_RUN_PATH' environment variable
         during linking
       - use the '-Wl,-rpath -Wl,LIBDIR' linker flag
       - have your system administrator add LIBDIR to '/etc/ld.so.conf'
    
    See any operating system documentation about shared libraries for
    more information, such as the ld(1) and ld.so(8) manual pages.
    
    ...
    ...
    $  gcc hello-world.c -o hello -levent

可以看到libevent被安装在`/usr/local/lib`。

# 动态库问题 #

$ cd /etc/ld.so.conf.d
    $ ls
    i386-linux-gnu.conf  libc.conf  x86_64-linux-gnu.conf

解决方法  
修改`etc/ld.so.conf`文件。  
a. 动态库路径添加到该文件中 - 绝对  
b. sudo ldconfig  
查看

$ cat libc.conf 
    # libc default configuration
    /usr/local/lib