You might want to look into the module Tie::File which comes with perl 5.8. Alternatively, use something like

open my $fh => $file or die "Failed to open $file: $!\n";
my $last = "";
while (<$fh>) {
    print "$last$_" if /ALARM:/;
    $last = $_;
}
close $fh;

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Abigail

In reply to Re: when reading a file how to print a line one above the current line?? by Abigail-II
in thread when reading a file how to print a line one above the current line?? by Anonymous Monk

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