每5秒运行脚本文件

每5秒运行脚本文件

Ubuntu 上操作

编辑crontab文件

vi /etc/crontab 

增加crontab 文件中命令，由于crontab文件最短1分钟运行一次，所以文件中分行5s运行一行

btw，确保tmp文件夹存在

# /etc/crontab: system-wide crontab
# Unlike any other crontab you don't have to run the `crontab'
# command to install the new version when you edit this file
# and files in /etc/cron.d. These files also have username fields,
# that none of the other crontabs do.

SHELL=/bin/sh
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin

# Example of job definition:
# .---------------- minute (0 - 59)
# |  .------------- hour (0 - 23)
# |  |  .---------- day of month (1 - 31)
# |  |  |  .------- month (1 - 12) OR jan,feb,mar,apr ...
# |  |  |  |  .---- day of week (0 - 6) (Sunday=0 or 7) OR sun,mon,tue,wed,thu,fri,sat
# |  |  |  |  |
# *  *  *  *  * user-name command to be executed
17 *    * * *   root    cd / && run-parts --report /etc/cron.hourly
25 6    * * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )
47 6    * * 7   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.weekly )
52 6    1 * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.monthly )
#
#增加行数这里开始
*/1 * * * * /bin/date >>/tmp/date.txt
*/1 * * * * sleep 5  && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 10 && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 15 && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 20 && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 25 && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 30 && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 35 && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 40 && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 45 && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 50 && /bin/date >>/tmp/date.txt
*/1 * * * * sleep 55 && /bin/date >>/tmp/date.txt

按:wq保存退出后，执行以下命令运行脚本文件

crontab /etc/crontab

查看脚本效果

tail -300f /tmp/date.txt

效果如下

root@ubuntu:/home# tail -300f /tmp/date.txt
Thu 08 Jul 2021 08:09:01 PM PDT
Thu 08 Jul 2021 08:09:06 PM PDT
Thu 08 Jul 2021 08:09:11 PM PDT
Thu 08 Jul 2021 08:09:16 PM PDT
Thu 08 Jul 2021 08:09:21 PM PDT
Thu 08 Jul 2021 08:09:26 PM PDT
Thu 08 Jul 2021 08:09:31 PM PDT
Thu 08 Jul 2021 08:09:36 PM PDT
Thu 08 Jul 2021 08:09:41 PM PDT
Thu 08 Jul 2021 08:09:46 PM PDT
Thu 08 Jul 2021 08:09:51 PM PDT
Thu 08 Jul 2021 08:09:56 PM PDT
Thu 08 Jul 2021 08:10:01 PM PDT
Thu 08 Jul 2021 08:10:06 PM PDT
Thu 08 Jul 2021 08:10:11 PM PDT
Thu 08 Jul 2021 08:10:16 PM PDT
Thu 08 Jul 2021 08:10:21 PM PDT
Thu 08 Jul 2021 08:10:26 PM PDT
Thu 08 Jul 2021 08:10:31 PM PDT
Thu 08 Jul 2021 08:10:36 PM PDT
Thu 08 Jul 2021 08:10:41 PM PDT
Thu 08 Jul 2021 08:10:46 PM PDT
Thu 08 Jul 2021 08:10:51 PM PDT
Thu 08 Jul 2021 08:10:56 PM PDT
Thu 08 Jul 2021 08:11:01 PM PDT
Thu 08 Jul 2021 08:11:06 PM PDT
Thu 08 Jul 2021 08:11:11 PM PDT
Thu 08 Jul 2021 08:11:16 PM PDT
Thu 08 Jul 2021 08:11:21 PM PDT
...

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