With PerlIO::via you can add a layer that converts whatever you want to line feeds. For example, if you want to accept CR and LF as line feeds:

package PerlIO::via::normeol;
sub FILL
{   
    my ($obj,$fh) = @_;
    my ($c);
    my $n = read ($fh, $c, 1);
    return undef unless $n;
    $c =~ tr/\r/\n/;
    return $c;
}
1;


use PerlIO::via::normeol;
open (A, "<:via(normeol)", "foo.bar");
while (<A>) {
 ...
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