In your original program, you slurped the whole file into memory using 

@DNA= <DNAFILE>

[download]
and then used the array @DNA for processing the data. Of course it would be better to write your program in a way that it reads only one line at a time, but if the logic of your application already assumes that you have the data in an array, and your program is already working well, trying Tie::File doesn't cost much, because you don't have to change a lot. Instead of opening and reading the file, you would use 
tie @DNA, 'Tie::File', "your_filename_goes_here", OPTIONS_GO_HERE or d
+ie "Can not tie file ($!)";

[download]
In any case, have a look at the mode option.

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Re: Seeking help for using Tie : : File in my perl program for counting bases using Active Perl 5.10.1 Build 1007 by rovf
in thread Seeking help for using Tie : : File in my perl program for counting bases using Active Perl 5.10.1 Build 1007 by supriyoch_2008

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