linux process alive
A: To send signal 0 to the process by pid, if the process is alive, it will return 0. as signal 1 has a name HUP, signal 0 also has a name EXIT. when a process exit normally, it send a signal 0. funcation atexit take advantage of this signal, and use it to install cleanup function. trap command in shell also use it to some cleanup. another usage is use it to detect a process is dead or not, you ca...
by coolper - Linux文档专区 - 2009-03-12 21:31:37 阅读（694） 回复（0）
linux 下的socket keep alive 测试 今天做了linux下设置socket的keep alive属性测试，采用阻塞模式下的C/S 结构模拟实验，测试结果似乎不是预期的效果。 测试用例：TCP socket连接，server端设置socket的keep alive属性，与客户端的连接建立之后，服务器发送数据到客户端。发送数据的过程中，拔服务器端的网线， 查看服务器的socket send结果。 测试结果：如果不设置socket的发送超时，发送操作一直阻塞（测试大约30分钟）。设...
雖然跑linux 無法做到real-time 我想知道假如我有3個應用程式同時執行且不會停止， linux 如何分配process1/2/3 執行時間? process1 -> context switch -> process2 -> context switch -> process3 -> context switch -> process1
As its name implies, the state field of the process descriptor describes what is currently happening to the process. It consists of an array of flags, each of which describes a possible process state. In the current linux version, these states are mutually exclusive, and hence exactly one flag of state always is set; the remaining flags are cleared. The following are the possible process states: ...
Take a guided tour from the Master Boot Record to the first user-space application Level: Introductory M. Tim Jones ( [email=mtj@mtjones.com?subject=Inside the linux boot process&cc=tomyoung@us.ibm.com]mtj@mtjones.com[/email] ), Consultant Engineer, Emulex 31 May 2006 The process of booting a linux® system consists of a number of stages. But whether you're booting a standard x86 desktop or a...
Inside the linux boot process Take a guided tour from the Master Boot Record to the first user-space application Document options Print this page E-mail this page Document options requiring JavaScript are not displayed New site feature dW radio -- Listen to our podcasts Rate this page Help us improve this content Level: Introductory M. Tim Jones ( [email=mtj@mtjones.com?subject...
这一节主要介绍了，内核创建一个子进程的过程。介绍了创建一个进程需要的十八个步骤。 Creating processes Unix operating systems rely heavily on process creation to statify user requests.As an example,the shell process creats a new process that executes another copy of the shell whenever the user enters a command. Traditional unix systems treat all processes in the same way:resources owned by the par...
这一节，主要描述了进程切换的过程。讲的十分清楚：） process Swithing In order to control the execution of processes,the kernel must be able to suspendthe execution of the process running on the cpu and resume the execution of some other process previously suspended.this activity is called process switching ,task switching,or context switching.the following sections describe the element of process...
这一节，主要介绍了进程描述符的数据结构，其中重要介绍了，进程状态，task数组以及相应的操作，进程链表，和pidhash table and chained lists，The list of task free entries，Parenthood Relationships Among process 和Wait Queues。 Charpter 3 process A process is usually defined as an instance of a program in execution. process Descriptor in order to manage process ,the kernel must have a clear picture of w...
When parent cannot handle the exited child process, the child process becomes a zombie, also known as a defunct process. The defunct process uses a little resource. It cannot be killed by kill(). It exists in all the system life. Then how to kill a zombie process? There are several ways to kill a zombie process or avoid to generate a zombie process as follows: 1. Kill the parent to eliminate the z...
