G'day lddzjwwy,

Perhaps something along these lines:

$ perl -Mstrict -Mwarnings -E '
    # Create test data
    use autodie qw{:all};
    use File::Temp;
    my $fh = File::Temp->new(UNLINK => 1);
    print $fh "qwe\rasd\003zxc\r123";
    seek $fh, 0, 0;

    # Read data splitting on "\r" or "\003"
    say for split /(?>\r|\003)/ => do { local $/; <$fh> };
'
qwe
asd
zxc
123
[download]

I assume you've picked "\003" purely as an example; I've used the same in the code above. However, using constructs like \o{...}, \x{...}, etc. may save you some interpolation issues down the track (see escape sequences in perlop - Quote and Quote-like Operators).