open my $fh, "<f1.txt" or do {
    print STDERR "can't open <f1.txt, but nevermind, I'll try f2.txt\n";
    open $fh, "<f2.txt" or die "still can't...";
};
print <$fh>; # this gives a warning "read on closed filehandle";


##</code><code>##

my $fh;
open $fh, "<f1.txt" or do {
    print STDERR "can't open <f1.txt, but nevermind, I'll try f2.txt\n";
    open $fh, "<f2.txt" or die "still can't...";
};
print <$fh>; # I see the content of f2.txt here ...