Sounds very much like you're trying to read a Fasta format sequence file?

You could use Bio::SeqIO, or if that is giving you problems you might try my crude Fasta load routine. It's the last code snippet in Re^5: Memory Usage in Regex On Large Sequence. That post/thread also shows a problem with the cpan module along with one reason why it's performance is not so good. Though that might have been fixed by now.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: How do I backtrack while reading a file line-by-line? by BrowserUk
in thread How do I backtrack while reading a file line-by-line? by mdunnbass

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