linux C++调用shell脚本 笔记一

1.使用vfork, 使用子进程调用脚本，注意子进程结束后，需要主动退出，否则可能会在退出此函数后，同父进程一样执行其它部分，若最后进入休眠状态，则可能成为杀不死的进程。

    pid_t pid;
    if ((pid = vfork()) < 0 )
    {
        nRet = -1;
		goto _exit_out;
    }
    else if ( pid == 0 )
    {
        m_nPid = getpid();
        char buffer[128];     
        memset(buffer, 0, sizeof(buffer));
        FILE* pipe = _POPEN(cmd, "r");
        if ( !pipe ){
            LOG_ERR(
                "Execute %s, error:%d\n",
                cmd, errno);
			nRet = -1;
			goto _exit_out;
        }
        LOG( 
            "------- Begin %s ------, pid is %d\n",
            cmd, m_nPid);
        while( !feof(pipe) ){
            if(fgets(buffer, 128, pipe)){
                sCmdOutput += string(buffer);
                LOG(  
                    "+ %s",
                    buffer);
            }
        }
        _PCLOSE(pipe);
        LOG( 
            "------- End   %s ------, pid is %d\n",
            cmd, m_nPid);
		exit(0);
    }
	else
	{
		int statusOfChild;
		wait(&statusOfChild);

		if (WIFEXITED(statusOfChild))
		{
			LOG(
	            "Child Process of %d terminated normally.\n",
	            m_nPid);
		}
		else
		{
			LOG( 
	            "Child Process of %d terminated unnormally, status is %d.\n",
	            m_nPid, statusOfChild);
		}
		
	    SNPRINTF(strCmd, 256, KILL_PID_INCLUDE_CHILD, m_nPid);
	    system(strCmd);
		
		LOG(
	            "Begin kill process by excute [%s]\n",
	            strCmd);
		
	    m_nPid = -2;
	}