Linux timed task management

before we know SSH Service Optimization and Client command operation, these are our basic services must be mastered, today we talk about Linux of Scheduled Tasks. As the name implies, some tasks are performed regularly. Like our alarm clock, timed alarm. I have a lot of time to use him later. So we have to play up the spirit, pay attention to, do not think he is very simple, not serious study. Needless to say, we already know the concept of timed tasks. How to write timed tasks under Linux, how to manage scheduled tasks This is the focus of my study. 650) this.width=650; "src=" Http://img.baidu.com/hi/ldw/w_0004.gif "alt=" w_0004.gif "/>

Linux task is also a service, the name of the service is called Crond, only by opening this service can we write our scheduled tasks, and through this service we can manage our scheduled tasks. Check to see if my Computer opens this service 650) this.width=650; "src=" Http://img.baidu.com/hi/ldw/w_0040.gif "alt=" W_0040.gif "/>

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See it! Here I use the chkconfig--list command to view the crond service at 3,4, 5 levels are powered on from the boot so my service is open, if you do not open this service can not use Scheduled Tasks Oh! How can I open him up when I need it? Look underneath .

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we are Linux all the services below can be started and switched off through the above command structure. Its command structure: service Name {stop,start,restart}. This is our simple service management. It's Convenient!

Service Management We know, then we'll talk about how to write a timed task. When writing a timed task, we first need to know what his format is! Look underneath .

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The above points is the meaning of the minute, when the meaning of the hour, day is the meaning of the day, the month is the month, week is the week. The following command is the task you are going to perform. 650) this.width=650; "src=" Http://img.baidu.com/hi/ldw/w_0039.gif "alt=" W_0039.gif "/>

Write timed tasks The most troublesome is in the expression of time, below I do a detailed explanation of the time expression:

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This is how time is expressed, and then we begin to write Linux timed tasks. It 's also easy to write timed tasks under Linux, using the crontab command to see the following

crontab Command Options :

- e edit a user's tasks

- R Delete a user's task

- L View Scheduled Tasks

I now write the example above to my server as follows

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How to view our editor's scheduled tasks, see below

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Similarly, we can also use the following direct view

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Delete Scheduled Tasks I don't have to say more, you edit that file directly, or you can use

Crontab-r commands are available.

The content of the scheduled task is so much, his main difficulty is the time expression. I hope you will make the time clear.

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Linux timed task management