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# 8  
Old 02-17-2012
The error message is because there is a $ missing off $previousSearch:

Code:
if [ $i -gt $previousSearch ]; then

# 9  
Old 02-20-2012
Livisbr, As i said i haven't tested and expected you to fix the run time issue if any... I have given you almost ready script.

here is the script with some fixes.

Code:
#!/bin/bash 
previousSearch=0 
while true; 
do
         Lines=$(cat  /var/adm/messages | grep -n ERROR | cut -d ":" -f1)  #to get the all lines numbers which has word ERROR
         for i in $Lines
         do
                 if [ $i -gt $previousSearch ]; then
                 line=$(expr $i + 1000)                             #get the maximun number of line which is needed
                 head -$line /var/adm/messages  | tail -2000 >> newfile.txt                   # get exact 2000 line, 1000 before ERROR and 1000 after ERROR
                 previousSearch=$i                                         # setting counter to last search result.
                 echo "---------------------------Next Search---------------------------" >> newfile.txt 
                 fi
         done
        sleep 30
 done

Last edited by vishal_vsh1; 02-20-2012 at 07:37 AM..
# 10  
Old 02-20-2012
Beware of using large values in a unix "tail" command. See "man tail" for limitations of the buffer size in "tail" on your system.

Code:
wc -l mylog
71520 mylog

tail -2000 mylog|wc -l
394

# 11  
Old 02-20-2012
Right Methyl...

livisbr, do you really need 1000 lines above and below the error? you can make it 100 or 200 that should be enough for you to get the cause of error.
# 12  
Old 03-19-2012
I hope this is done now.
# 13  
Old 03-19-2012
Why dont you try

Quote:
grep -A<n> "ERROR" < infile
print n number of lines after the line containing ERROR


Quote:
grep -B<n> "ERROR" < infile
print n number of lines before the line containing ERROR

Quote:
man grep
-A NUM, --after-context=NUM
Print NUM lines of trailing context after matching lines. Places a line containing --
between contiguous groups of matches.
-B NUM, --before-context=NUM
Print NUM lines of leading context before matching lines. Places a line containing --
between contiguous groups of matches.
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