Need help from script guru to compare two files and if there's any difference perform specific action.

cmp -s /etc/hosts /etc/passwd || date

Diff is a good tool for comparing files as to how to trigger an event on the output I think some more details of your problem or maybe an analogous example?

I setup an SMS gateway which is accessible via browser. I used curl to do this.

#curl -u userass http://someurl.html >> /tmp/somefile.txt

The file is on html format and I need to grep where the SMS messages is so I did

#cat /tmp/somefile.txt | grep -i "var sms"

The output example file as below:


var sms= ["11-27 08:34:28,SENDER,MESSAGE1","11-27 05:25:58,SENDER,MESSAGE2","11-27 05:25:58,SENDER,MESSAGE3"];

and so on and so forth.

What I want to do is to get output of this html and trim these SMS messages. Maybe a crontab every 10 or 15 minutes that will get the output via curl compare the previous file and if there is any change, send the output to an email. I would also need to parse the above value correctly so it will be easier to read in the email. Thanks.