Hello all, I am encountering some issue in trying to do the following in ksh88, therefore I want to explore a smart perl approach, but my knowledge is limited, can you help?
I have 2 files, the first (indexFile1) contains lines with start offset and length for each record inside the second file, so just 2 numbers separated by a space. The second file can be very large, each actual record start offset and length is defined by the entry in indexFile1. Since there are no records separators wc-l returns 0 for the second file, no matter how large its size actually is.
I want to gather all the records from the large file one at a time and write them out to a new file individually. What is the best way to approach this processing?
I suspect I will have trouble in ksh88 reading a whole large file into a variable (using awk) and then use a cut command on the variable contents to collect my record in the form: 
FileContent=$(awk '{print $0}' largeFile2) # this is where I think I h
+ave a problem :

# LINE contains start and offset identifying each record in largeFile2

while read LINE;do 
pass=1
for results in $LINE; do
if [[ $pass -eq 1 ]];then 
from=$results
pass=2
else to=$results
fi
done
(( from=$val1+1 ))
(( to=$val1+$val2 ))
newOut=$(echo $FileContent|cut -c $from-$to)
echo $newOut >> newfile
done < indexFile1

[download]
I have it working ok for small sizes of largeFile2. I can see a problem when the size of file2 gets large. I hope you can give me some suggestions on how to do this better. Thanks!

In reply to Read offset into other files by gio001

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