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Reading a file after nth line

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# 1  
Old 07-29-2011
Reading a file after nth line
I know how to read a file line by line. But don't to how to skip to a line matching a criteria and then continue reading it till the end.

This is a log file. The input is a timestamp.
1. Find the timestamp in the log file
2. Read the remaining lines one at a time till EOF.

How can I do this?
# 2  
Old 07-29-2011
Code:
sed -ne '/timestamp/,$p' yourfile

This User Gave Thanks to pludi For This Post:
avinthm
# 3  
Old 07-29-2011
Quote:
Originally Posted by pludi
Code:
sed -ne '/timestamp/,$p' yourfile

you mean, p will have the rest of the file and i read it line by line?
# 4  
Old 07-29-2011
No. It's a sed script, telling it not to print the contents of the file, until the timestamp is found. From there on to the rest, print the file as it is.
# 5  
Old 07-29-2011
Ok here is my code
Code:
while read line
        do
                        processLine
        done < $logFile

Now where and how does your statement fit here?

---------- Post updated at 05:49 PM ---------- Previous update was at 05:34 PM ----------

I haven't worked much in unix, so finding it hard to perform simple operations
Last edited by radoulov; 08-01-2011 at 04:14 AM.. Reason: Code tags.
# 6  
Old 07-29-2011
If you want to do some "processing" on lines read after "timestamp" occured,

Code:
 
sed -ne '/'"${timestamp}"'/,$p' yourfile | while read line 
do
## do processing
done

Last edited by panyam; 07-29-2011 at 10:23 AM.. Reason: Changed as per requirement
This User Gave Thanks to panyam For This Post:
avinthm
# 7  
Old 07-29-2011
Quote:
Originally Posted by panyam

Code:
 
sed -ne '/timestamp/,$p' yourfile | while read line 
do
## do processing
done

I am trying use a variable for timestamp like
Code:
sed -ne '/$timestamp/,$p' yourfile | while read line

And sed is not matching any records. I tried '$timestamp', "$timestamp"....nothing seems to be working.

---------- Post updated at 06:53 PM ---------- Previous update was at 06:48 PM ----------

I tried
Code:
sed -ne '/2011\/06\/28 11\:16\:14/,$p' test.log

on command prompt and it works fine.
Last edited by radoulov; 08-01-2011 at 04:15 AM.. Reason: Code tags.
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