Perl has a default method of reading a file one line at a time, you can then process this line and write it back out to a new file. 

open FILE_HANDLE, "<", $File_Name or die "probs opening $File_Name: $!
+\n";
while (<FILE_HANDLE>) { # defaults to one line at a time
    # do something to this line that is now
    # contained in the $_ variable
}

[download]
You can tell perl to use any string of characters as an input record seperator (the $/ variable) and then read your file one record at a time, this defaults to the end of line character for your OS so perl reads the file line at a time. 
# imagine each record starts with "New Record"
local $/="New Record";
open FILE_HANDLE, "<", $File_Name or die "probs opening $File_Name: $!
+\n";
while (<FILE_HANDLE>) {
    # do something to this block now
    # contained in the $_ variable
}

[download]

There are also various modules that tie a file on disk to a data structure without reading it all in. This may also be helpful. Have a look at Tie::File for instance.

If you give some more specific details of what you are trying to do we can give more help.

Cheers,
R.

Pereant, qui ante nos nostra dixerunt!

In reply to Re: how can i work with huge files? by Random_Walk
in thread how can i work with huge files? by morfeas

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