pid

Operating System 作业-02

。_饼干妹妹 提交于 2019-11-30 17:43:35
4.3、在统一进程的多线程之间,下列哪些程序状态部分会被共享? 堆内存和全局变量 4.5、第三章讨论了Google的chrome浏览器,以及在单独进程中打开每个新网站的做法。如果chrome设计成在单独线程中打开每个新网页,那么会有什么样的好处? 每个标签页都会启动一个独立的进程,这样即使因为某个页面崩溃了也不会影响到其他页面。 4.9、具有2个双核处理器的系统有4个处理核可用于调度。这个系统有一个cpu密集型应用程序运行。在程序启动时,所有输入通过打开一个文件而读入。同样,在程序终止前,所有程序输出的结果都写入一个文件。在程序启动和终止之间,该程序为cpu密集型。你的任务是通过多线程技术来提高这个应用程序的性能。这个应用程序运行在采用一对一线程模型的系统。 (1)、你将创建多少个线程,用于执行输入和输出?请解释。 线程数取决于应用程序的要求,因此创建一个线程用于执行输入和输出就足够了。 (2)、你将创建多少个形成,用于应用程序的cpu密集型部分?请解释。 线程数应该和处理核数是一样的,因此要创建四个线程。 4.10、考虑下面的代码 a.创建了多少个单独的进程? b.创建了都少个单独的线程? 创建了5个单独的进程 创建了2个单独的线程。 4.15、修改第三章的习题3.13.这个修改包括写一个多线程程序,以测试你的习题3.13的解决方案 #include <stdlib.h>

What is the correct printf specifier for printing pid_t

强颜欢笑 提交于 2019-11-30 16:47:58
I'm currently using a explicit cast to long and using %ld for printing pid_t , is there a specifier such as %z for size_t for pid_t ? If not what the best way of printing pid_t ? There's no such specifier. I think what you're doing is fine… you could use an even wider int type, but there's no implementation where pid_t is bigger than long and probably never will be. With integer types lacking a matching format specifier as in the case of pid_t , yet with known sign-ness, cast to widest matching signed type and print. If sign-ness is not known, cast to the widest unsigned type. pid_t pid = foo(

Address localhost:1099 is already in use

早过忘川 提交于 2019-11-30 16:04:24
今天使用IDEA启动项目的时候,报了下列错误: Address localhost:1099 is already in use 问题分析 这是端口号被占用了,已经有其他应用正在使用这个端口号 问题解决 方式一: 按快捷键 Ctrl+Shift+Esc 打开任务管理器,找到java.exe,然后点击“结束任务”即可! 方式二: 这种方式适用于所有端口被占用的情况: step1:通过端口找到PID 打开dos命令行,输入netstat -ano | find "1099",得到下列内容,看到最后一列是9280,就是PID: step2:通过PID找到进程 输入:tasklist | find "9280"(双引号里面的是PID) step3:关闭进程 输入命令关闭进程:taskkill /f /t /im java.exe 原文链接:https://blog.csdn.net/qq_26230421/article/details/80098032 来源: https://www.cnblogs.com/share-record/p/11603136.html

How to find out which Node.js pid is running on which port

南笙酒味 提交于 2019-11-30 15:04:50
问题 I'd like to restart one of many Node.js processes I have running on my server. If I run ps ax | grep node I get a list of all my Node proccesses but it doesn't tell me which port they're on. How do I kill the one running on port 3000 (for instance). What is a good way to manage multiple Node processes? 回答1: If you run: $ netstat -anp 2> /dev/null | grep :3000 You should see something like: tcp 0 0 0.0.0.0:3000 0.0.0.0:* LISTEN 5902/node In this case the 5902 is the pid. You can use something

Kill a java process (in linux) by process name instead of PID

一世执手 提交于 2019-11-30 14:44:59
问题 While configuring/installing Hadoop cluster we often need to kill a Java Process/Daemon. We see Java Processes/Daemons running with jps command. Usually we kill a Java process with its PID. E.g. kill -9 112224 It is little bit difficult to type the PID. Is there a way to kill the process by its name? In a single command? 回答1: Here is the command to kill the Java process by is Process Name instead of its ProcessID. kill `jps | grep "DataNode" | cut -d " " -f 1` Let me explain more, about the

Find PID of browser process launched by Selenium WebDriver

雨燕双飞 提交于 2019-11-30 14:39:58
In C# I start up a browser for testing, I want to get the PID so that on my winforms application I can kill any remaining ghost processes started driver = new FirefoxDriver(); How can I get the PID? Looks more like a C# question, instead of Selenium specific. This is a very old non-deterministic answer, please reconsider if you want to try this out. My logic would be you get all process PIDs with the name firefox using Process.GetProcessesByName Method , then start your FirefoxDriver , then get the processes' PIDs again, compare them to get the PIDs just started. In this case, it doesn't

How to get child PID in C?

故事扮演 提交于 2019-11-30 13:54:46
问题 I'm creating child processes in a for -loop. Inside the child process, I can retrieve the child PID with getpid() . However, for some reason when I try to store the value of getpid() into a variable declared by the parent process, the change is nullified when I check for it in the parent process. I'm assuming this has to do with some sort of process variable scope. Not really familiar with C, so can't be too sure. Anyhow what is a way of storing the result of getpid() of a child PID (when

How to tie a network connection to a PID without using lsof or netstat?

吃可爱长大的小学妹 提交于 2019-11-30 12:59:42
Is there a way to tie a network connection to a PID (process ID) without forking to lsof or netstat? Currently lsof is being used to poll what connections belong which process ID. However lsof or netstat can be quite expensive on a busy host and would like to avoid having to fork to these tools. Is there someplace similar to /proc/$pid where one can look to find this information? I know what the network connections are by examining /proc/net but can't figure out how to tie this back to a pid. Over in /proc/$pid, there doesn't seem to be any network information. The target hosts are Linux 2.4

vue与element ui的el-checkbox的坑

别说谁变了你拦得住时间么 提交于 2019-11-30 12:57:51
一,场景 通过使用checkbox,实现如图的场景, 点击某个tag,实现选中和非选中状态。 二, 官网的例子 通过切换checked值为true或者false来实现,一个checkbox的状态切换 <template> <!-- `checked` 为 true 或 false --> <el-checkbox v-model="checked">备选项</el-checkbox> </template> <script> export default { data() { return { checked: true }; } }; </script>   效果如下: 三, 思考。 通过循环li, 给数据添加checked属性,并绑定到v-model上,来实现 一的场景。模板代码如下: <template> <div class="demo"> <ul> <li v-for="(item, index) in list" :key="index"> //循环li <el-checkbox v-model="item.checked"> //v-model绑定到每个item的checked属性 {{ item.name }} </el-checkbox> </li> </ul> </div> </template> 后台返回数据格式(已精简),如下(没有checked属性) [

linux netlink通信机制简介

此生再无相见时 提交于 2019-11-30 12:23:32
一、什么是Netlink通信机制   Netlink套接字是用以实现 用户进程与内核进程 通信的一种特殊的进程间通信(IPC) ,也是网络应用程序与内核通信的最常用的接口。 Netlink 是一种特殊的 socket,它是 Linux 所特有的,类似于 BSD 中的AF_ROUTE 但又远比它的功能强大,目前在Linux 内核中 使用netlink 进行应用与内核通信的应用很多; 包括:路由 daemon(NETLINK_ROUTE),用户态 socket 协议(NETLINK_USERSOCK), 防火墙(NETLINK_FIREWALL),netfilter 子系统(NETLINK_NETFILTER),内核事件向用户态通知(NETLINK_KOBJECT_UEVENT), 通用 netlink(NETLINK_GENERIC)等。 Netlink 是一种在内核与用户应用间进行双向数据传输的非常好的方式,用户态应用使用标准的 socket API 就可以使用 netlink 提供的强大功能, 内核态需要使用专门的内核 API 来使用 netlink。 Netlink 相对于 系统调用 , ioctl 以及 /proc文件系统 而言具有以下优点: 1,netlink使用简单,只需要在include/linux/netlink.h中增加一个新类型的 netlink 协议定义即可,