The primary problem is that you're only reading one line from the file at a time. That's why it breaks for multi-line entries. You have a couple of solutions: 
# read the whole file at once
# XXX: updated (thanks, jmcnamara and VSarkiss)
{ local $/; $file = <IN>; }
@titles = $file =~ /_\[\d]([^_]*)/g;

[download]
or you could employ some logic: 
# read more lines as needed
while (<IN>) {
  if (/_\[\d]([^_]*)_/) {
    push @titles, $1;
  }
  elsif (/_\[\d]([^_]*)/) {
    push @titles, $1;
    while (<IN>) {
      if (/([^_]*)/) { $titles[-1] .= $1 }
      last if /_/;
    }
  }
}

[download]
I think the first approach is easier to understand, generally.

_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker, who'd like a job (NYC-area)
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

In reply to Re: how to reg-exp match across multiple lines? by japhy
in thread how to reg-exp match across multiple lines? by Anonymous Monk

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