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With script bash, read file line per line starting at the end


 
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# 1  
Old 01-19-2016
With script bash, read file line per line starting at the end

Hello,

I'm works on Ubuntu server

My goal : I would like to read file line per line, but i want to started at the end of file.

Currently, I use instructions :
Code:
while read line;
do
COMMAND
done < /var/log/apache2/access.log

But, the first line, i don't want this. The file is long so, i would like to start at the end of file.

I'm available for your questions.

Thanks.

Last edited by vbe; 01-19-2016 at 08:18 AM.. Reason: code tags...
# 2  
Old 01-19-2016
Did you consider the tac command?
This User Gave Thanks to RudiC For This Post:
# 3  
Old 01-19-2016
Quote:
Originally Posted by Fuziion
Hello,

I'm works on Ubuntu server

My goal : I would like to read file line per line, but i want to started at the end of file.

Currently, I use instructions :
Code:
while read line;
do
COMMAND
done < /var/log/apache2/access.log

But, the first line, i don't want this. The file is long so, i would like to start at the end of file.

I'm available for your questions.

Thanks.
Perhaps, modifying what you have already:

Code:
tac /var/log/apache2/access.log | while IFS= read line; do
    COMMAND using line
done

This User Gave Thanks to Aia For This Post:
# 4  
Old 01-19-2016
If tac is not available try:

Code:
tail -r file

or
Code:
sed '1!G;h;$!d' file

See here:
https://www.unix.com/302888137-post4.html
These 2 Users Gave Thanks to Scrutinizer For This Post:
# 5  
Old 01-19-2016
You are in Ubuntu which by default it has tac, but in case you do not want to use it, you may use the other alternatives.

Let's give you one more:

Code:
perl -e 'print reverse <>' /var/log/apache2/access.log | while IFS= read line; do
    COMMAND using line
done

This User Gave Thanks to Aia For This Post:
# 6  
Old 01-20-2016
Thanks for your answer.

I don't know "tac". He works with my script. GOOD SmilieSmilieSmilie

Bye.

---------- Post updated at 12:08 PM ---------- Previous update was at 12:07 PM ----------

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