If you read all lines into an array, you can use a list slice or splice to pull out chunks of text: 
open(INFILE, $filename) or die "Can't open $filename: $!";
my @lines = <INFILE>;
my @chapters;
$chapters[1] = @lines[0 .. 55];
$chapters[2] = @lines[56 .. 112];

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There are more idiomatic ways to do that, but it'll get you started.

Update: merlyn's right. That's what happens when you switch approaches while typing out your code. If you don't want to use references, do instead: 

@chapter1 = @lines[0 .. 55];
@chapter2 = @lines[56 .. 112];

[download]
In general, I'd discourage that approach, because appending numbers to variable names is a warning sign. In this case, it's not a big deal.

In reply to Re: How do I split a file by lines into smaller files by chromatic
in thread How do I split a file by lines into smaller files by PatrioticDreamer

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