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Opening Large Files Question

Opening Large Files Question

Opening Large Files Question

I am currently looking at opening large files, wondered if someone could answer a query.

CODE --> perl

open (FILE, '<', $file) or die "$!\n";
while (<FILE>) {
*Do stuff with line

a) When you use "open" does this read the whole file in before I start reading line by line?
b) If it does open the whole file is there a simple way to only open the last part of the file?

RE: Opening Large Files Question

Now looking at "File::ReadBackwards.pm -- Read a file backwards by lines"

Quote (cpan.org)

It works by reading a large (8kb) block of data from the end of the file. It then splits them on the record separator and stores a list of records in the object. Each call to readline returns the top record of the list and if the list is empty it refills it by reading the previous block from the file and splitting it. When the beginning of the file is reached and there are no more lines, undef is returned. All boundary conditions are handled correctly i.e. if there is a trailing partial line (no newline) it will be the first line returned and lines larger than the read buffer size are handled properly.

This was exactly what I was looking for, posted solution to help others

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