It's not clear what you want. A construct like: 
while (<>) {
    if (/begin/ ... /end/) {
        ...
    }
}

[download]
still reads the entire file, line-by-line. If your file consists of 'records' that start with ^lmo\d+, and end with the next occurence, playing with the range operator doesn't make much sense; you might as well do a straigth while (<>) { ... } loop.

What is it what you really want?

Abigail

In reply to Re: extract regions by Abigail-II
in thread extract regions by Murcia

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