libevent编译问题

官网下载：https://libevent.org/
直接地址：https://github.com/libevent/libevent/releases/download/release-2.1.12-stable/libevent-2.1.12-stable.tar.gz

解压后编译，遇到如下问题，重装openssl也不行：

[root@localhost libevent-2.1.12-stable]# ./configure 
此处省略...
configure: error: openssl is a must but can not be found. You should add the directory containing `openssl.pc' to the `PKG_CONFIG_PATH' environment variable, or set `CFLAGS' and `LDFLAGS' directly for openssl, or use `--disable-openssl' to disable support for openssl encryption
[root@localhost libevent-2.1.12-stable]# make
make: *** 没有指明目标并且找不到 makefile。 停止。
[root@localhost libevent-2.1.12-stable]# 

直接按照提示加了–disable-openssl就可以编译了

配置：

./configure --disable-openssl

如需要可以指定目录，则后续编译请指定库目录：
./configure -prefix=/usr/lib/libevent --disable-openssl

编译：

make && make install

查看安装与否：

ls -al /usr/lib | grep libevent

注意：如果编译时，发现找不到定义，请查看环境变量问题

测试 用例：

#include <iostream>

#include <event.h>
#include <time.h>

struct event ev;
struct timeval tv;

void timer_cb(int fd, short envent, void *arg)
{
    
    
        std::cout << "timer_cb" << std::endl;
        event_add(&ev, &tv);
}

int main()
{
    
    
        struct event_base *base = event_init();
        tv.tv_sec = 1;
        tv.tv_usec = 0;

        event_set(&ev, -1, 0, timer_cb, NULL);
        event_base_set(base, &ev);
        event_add(&ev, &tv);
        event_base_dispatch(base);
        return 0;
}

编译（将源码中的头文件拷贝到测试代码的目录）：

[root@localhost test]# ls
a.out  compile.sh  include  libeventTest.cpp
[root@localhost test]# cat compile.sh
#!/bin/sh
g++ --static -I ./include libeventTest.cpp -levent
[root@localhost test]#

学习文档：https://www.bookstack.cn/read/libevent/450ef2232c710e15.md