How To Create A Log File In Shell Script

08-09-2005, 07:28 AM

I'm currently making a bash script to untar and configure apache, mysql php4 and a few other programs, but i'm having trouble with the script and need to be able to find where the errors are.

But the problem is so much output information comes up on the screen and i can only move up a few screens lengths, is there some code i can put into the script that create a log file from the screen output.

08-09-2005, 10:42 AM

When you run your script, redirect the output to a file:

somescript &> somelogfile

If you need to see the output while it's writing to the file, you can 'tail -F' the file, or use tee:

somescript 2>&1 | tee somelogfile

08-10-2005, 07:23 AM

To put output in logfile:
script > logfile

To put output and errors in logfile:
script 2>&1 > logfile

To separate:
script 1> logouput 2> logerror

08-10-2005, 08:21 AM

Or, from inside the script itself:
exec 1>/path/to/logfile 2>&1

Yves.

08-10-2005, 06:47 PM

Thanks for the replies everyone, macemoneta solution worked like a treat. I'll try the others as well, print a copy of this page to have as a reference, which will come in hand since i've Just started learning PHP programming.

theYinYeti, exec 1>/path/to/logfile 2>&1

I take it this goes at the very top of the script.

08-11-2005, 03:29 AM

Oops sorry! I overlooked the "PHP" aspect of your first post
What I wrote only applies to shell (bash at least) scripts, not PHP. Other solutions do apply to any scripts however, because they happen in the bash side of things even if the script itself is PHP.

Yves.

08-11-2005, 04:55 AM

theYinYeti

No you were right the first time, the script i'm working on is for a bash script. At college we are lerning how to install Apache, Mysql and PHP4 on one machine, and the other machine already has a webserver running were we upload are webpages and test a PHP scripts.

I just wanted to make a script to help with the installation process since it will be part of the practical test coming up in a few weeks. And since php can run linux console commands, I thought these would be a nice addition

09-27-2009, 03:40 PM

where should i put "script 2>&1 > logfile" ,"script 1> logouput 2> logerror" ? in script itself or cron job?

tq

09-28-2009, 04:42 AM

Quote:

Originally Posted by unknown_friends View Post

where should i put "script 2>&1 > logfile" ,"script 1> logouput 2> logerror" ? in script itself or cron job?

tq

Depends, you can run it from inside the script, just place it at the very top of the script.

Quote:

exec 1>/path/to/logfile 2>&1

Or you can run it when you run a cron job from crontab like this.

Quote:

* 3 * * * /path/to/script 2>&1 > /path/to/logfile.txt

08:49 AM

This is a quite old thread but i will give my two cents anyway.
Many times I create a function that writes a logfile and I call it whenever I want:

Code:

logprint() {     echo "$(date +%T): $*" >> $LOGFILE }

I start my script with writing the date:

Code:

echo "---------- Log of $0 for $LOGDATE ----------" >> $LOGFILE

and then I call logprint whenever i want in the script:

Code:

... logprint "$1 : successfully compressed, Size: $thissize" ... logprint "$0: Checking for backups older than $DAYSTOKEEP days to delete"

So I get a logfile that is devided into days and each line has also the time.

03-26-2012, 06:33 AM

hi all
i am running the script and a cron to take the backup every day at some time.
i like to create logfile automatically all the time when cron runs and logfile name shpuld contain the date so we can easily locate it.
and also like to write into output of terminal (about backup process) into newly created log file

thank you

03-27-2012, 07:39 AM

Hello,

to create a new file every time the cronjob runs you can add it in your script.
For example

Code:

FILEDATE=`date +%F` LOGFILE=/var/log/backup.$FILEDATE.log touch $LOGFILE  echo "message $variable message"  >> $LOGFILE

How To Create A Log File In Shell Script