Linux下面的任務部署大家都知道是利用crontab來實現的，至於crontab的一些類型我這里就不詳細的來闡述，例如：
-e (edit user's crontab)--編輯當前的計划任務
-l (list user's crontab)--查看當前的計划任務
-r (delete user's crontab)--刪除當前的計划任務
-ri (prompt before deleting user's crontab)--刪除前給出確認,-r的話就是直接刪除，通常使用下面的，-ri刪除操作危險
king@ubuntu:/$ crontab -ri
crontab: really delete king's crontab? (y/n)
--提示你是否刪除
格式：
大概的語法知道了，下面我們就從一個0起步的人做起，此時我們的系統里面的計划任務就是一個空白，沒有設置任何計划任務，也可以創建一個新用戶登錄查看
step1:以study 用戶登錄執行crontab -l命令
study@ubuntu:/$ crontab -l
# Edit this file to introduce tasks to be run by cron.
#
# Each task to run has to be defined through a single line
# indicating with different fields when the task will be run
# and what command to run for the task
#
# To define the time you can provide concrete values for
# minute (m), hour (h), day of month (dom), month (mon),
# and day of week (dow) or use '*' in these fields (for 'any').#
# Notice that tasks will be started based on the cron's system
# daemon's notion of time and timezones.
#
# Output of the crontab jobs (including errors) is sent through
# email to the user the crontab file belongs to (unless redirected).
# For example, you can run a backup of all your user accounts
# at 5 a.m every week with:
# 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/
#
# For more information see the manual pages of crontab(5) and cron(8)
#
# m h dom mon dow command
study@ubuntu:/$
可以看出最后面的不帶#注釋后面什么也沒有，切換一個用計划任務的用戶king,再次執行crontab -l
# Edit this file to introduce tasks to be run by cron.
#
# Each task to run has to be defined through a single line
# indicating with different fields when the task will be run
# and what command to run for the task
#
# To define the time you can provide concrete values for
# minute (m), hour (h), day of month (dom), month (mon),
# and day of week (dow) or use '*' in these fields (for 'any').#
# Notice that tasks will be started based on the cron's system
# daemon's notion of time and timezones.
#
# Output of the crontab jobs (including errors) is sent through
# email to the user the crontab file belongs to (unless redirected).
#
# For example, you can run a backup of all your user accounts
# at 5 a.m every week with:
# 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/
#
# For more information see the manual pages of crontab(5) and cron(8)
#
# m h dom mon dow command
*/2 * * * * date >>/home/king/b1/time.txt
king@ubuntu:/$
大家可以清楚的看到這一行：*/2 * * * * date >>/home/king/b1/time.txt
這個就是一個每隔2分鍾讀取當前時間輸出到/home/king/b1/time.txt這個文件中，下面我們切換回study用戶
crontab -e
# Edit this file to introduce tasks to be run by cron.
#
# Each task to run has to be defined through a single line
# indicating with different fields when the task will be run
# and what command to run for the task
#
# To define the time you can provide concrete values for
# minute (m), hour (h), day of month (dom), month (mon),
# and day of week (dow) or use '*' in these fields (for 'any').#
# Notice that tasks will be started based on the cron's system
# daemon's notion of time and timezones.
#
# Output of the crontab jobs (including errors) is sent through
# email to the user the crontab file belongs to (unless redirected).
# For example, you can run a backup of all your user accounts
# at 5 a.m every week with:
# 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/
#
# For more information see the manual pages of crontab(5) and cron(8)
#
# m h dom mon dow command
~
"/tmp/crontab.Aulssl/crontab" 22L, 886C
我們發現不能編輯，此時就要切換一下到編輯模式：i 進入編輯模式 輸入
*/1 * * * * date >>/home/study/test/testdate.txt
然后按Esc退出編輯模式
然后按Shift+: 保存
然后按wq 退出
編輯成功 crontab -l 查看我們編輯的任務
# Edit this file to introduce tasks to be run by cron.
#
# Each task to run has to be defined through a single line
# indicating with different fields when the task will be run
# and what command to run for the task
#
# To define the time you can provide concrete values for
# minute (m), hour (h), day of month (dom), month (mon),
# and day of week (dow) or use '*' in these fields (for 'any').#
# Notice that tasks will be started based on the cron's system
# daemon's notion of time and timezones.
#
# Output of the crontab jobs (including errors) is sent through
# email to the user the crontab file belongs to (unless redirected).
# For example, you can run a backup of all your user accounts
# at 5 a.m every week with:
# 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/
#
# For more information see the manual pages of crontab(5) and cron(8)
#
# m h dom mon dow command
*/1 * * * * date >>/home/study/test/testdate.txt
study@ubuntu:/$
OK 部署上去了，接着看部署執行效果 cd /home/study/test/
study@ubuntu:/$ cd /home/study/test
study@ubuntu:~/test$ cat testdate--這樣寫
cat: testdate: No such file or directory--提示不存在
study@ubuntu:~/test$ cat testdate.txt--cat 查看文件的全稱 ok
Wed Mar 6 11:57:01 CST 2013
Wed Mar 6 11:58:02 CST 2013
Wed Mar 6 11:59:01 CST 2013
Wed Mar 6 12:00:01 CST 2013
Wed Mar 6 12:01:01 CST 2013
study@ubuntu:~/test$
最后要強調的是每一個crontab是針對當前用戶的，用戶king 有自己的計划任務 用戶study也有自己的計划任務
可以看到 在文件夾里面已經按照每分鍾輸入格式顯示出來了。以上文章獻給初學者，共勉!