Quick start | Libevent

1.下载Libevent源码

$ git clone https://github.com/libevent/libevent.git

 

2. 创建Libevent本地安装目录 并 添加本地bin目录到环境变量PATH

$ export MY_INSTALL_DIR=$HOME/.libevent
$ mkdir -p $MY_INSTALL_DIR
$ export PATH="$MY_INSTALL_DIR/bin:$PATH

 

3. 构建并安装Libenvet

$ cd libevent
$ mkdir -p cmake/build
$ cd cmake/build
$ cmake -DCMAKE_INSTALL_PREFIX=$MY_INSTALL_DIR ../..
$ make
$ make install

 

4. 编译Hello world示例程序

设置pkg config查找路径：

$ export PKG_CONFIG_PATH=/home/suph/.libevent/lib/pkgconfig/

创建Makefile文件：

#Makefile
CXX = gcc
CPPFLAGS += `pkg-config --cflags libevent_core libevent_extra`
LDFLAGS += -L/usr/local/lib `pkg-config --libs libevent_core libevent_extra`\
           -pthread

all: hello-world 

hello-world: hello-world.o
    $(CXX) $^ $(LDFLAGS) -o $@

clean:
    rm -f *.o hello-world

 

5. 运行示例程序

直接运行hello-word例程，报如下错误：

$ ./hello-world 
./hello-world: error while loading shared libraries: libevent_core-2.1.so.7: cannot open shared object file: No such file or directory

产生原因：

    在运行时，程序无法找到libevent_core-2.1.so.7这个动态库。因为该动态库在安装时，存放的路径在/home/suph/.libevent/lib下，不在系统的默认查找路径内。

解决方法：

    将Libevent安装路径 加入到 系统查找路径内

    在/etc/ld.so.conf.d/目录下，新增mylib.conf文件，内容如下

$ cat /etc/ld.so.conf.d/mylib.conf 
# library path configuration for dynamic library
/home/suph/.libevent/lib