in reply to How to store large strings?

I can't assign the whole sequence to a variable.

That doesn't make any sense, This shows perl storing 6 billion characters in a single variable: 

[0] Perl> $a = 'x'x 1e6;;
[0] Perl> $a x= 6000;;
[0] Perl> print length $a;;
6000000000

[download]

So there is more to your problem than you are describing. The best thing you can do, is post the code that is giving you the problem.

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