B::Deparse is your friend in strange syntax corners. 

$ perl -MO=Deparse,-p,-q
# . . . your first example here
^D
unless (open(my $fh, '<f1.txt')) {
    do {
        print(STDERR "can't open <f1.txt, but nevermind, I'll try f2.t
+xt\n");
        (open($fh, '<f2.txt') or die(q[still can't...]));
    };
}
print(<$fh>);

[download]

So you can see now that $fh is scoped to the unless block that's been implicitly created.

Update: Not that that's not a little wierd, mind you. After looking at it a second time it's slightly surprising.

In reply to Re: "my $filehandle" scoping strange problem by Fletch
in thread "my $filehandle" scoping strange problem by vkon

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