How to implement second-level scheduled tasks with Linux Crontab Shell script

1. Write Shell script crontab.sh

#!/bin/bash 
step=1 #The number of seconds between steps cannot be greater than 60 
for (( i = 0; i < 60; i=(i+step) )); do 
 $(php '/home/www/php/crontab/crontab.php') 
 sleep $step 
done 
exit 0

2. Enter the following statement in crontab -e, then press :wq to save and exit

# mh dom monitor command 
* * * * * /home/www/php/crontab/crontab.sh

Linux second-level scheduled task implementation

Ideas:

Linux itself does not support second-level timing. To achieve this, you can run a script at a fixed time (for example, once every minute). The content of this script is actually an infinite loop execution code, that is, it keeps executing.

Note: If the time taken for a scheduled program to execute is too long, for example, it takes more than 1 second to execute, you need to seelp, that is, let the script sleep for a while in the infinite loop.

The following demonstrates a shell script's second-level timing task:

1.crontab -e executes the inviteFriend.sh script every minute

#2 seconds to run - Invite friends 3.0

 * * * * * /webservice/crontab/inviteFriend.sh

2.cd /webservice/crontab/ Switch to the directory vim inviteFriend.sh

Write the following content:

#!/bin/bash
step=2 #The number of seconds between steps cannot be greater than 60 

for (( i = 0; i < 60; i=(i+step) )); do
 #$(php '/home/php/crontab/tolog.php') 
 curl -I http://******.com/InviteFriends/sendInviteFriendCoupon
 sleep $step
done
exit 0

wqSave and exit

Note: After saving, you need to authorize the script.

chmod 777 filename

Summarize

The above is the method that I introduced to you to use Linux Crontab Shell script to implement second-level scheduled tasks. I hope it will be helpful to you. If you have any questions, please leave me a message and I will reply to you in time!