my $lflag = ( -l 'foo' ); # check before opening
$lflag or open my $fh, ">>foo" or ErrorHandler( $?, $! );
$lflag = ( -l 'foo' ); # and again after opening
unless( $lflag } {
    # process file
}
$lflag or close $fh;
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No, the whole point is that you can't guarantee that the thing the filename "foo" points to doesn't change between operations. You're only making it harder, not impossible, to mess with foo.

update see Re: opening files: link checking and race conditions for code that can cause your method to fail, and Re^2: opening files: link checking and race conditions for the best solution (even if it's not 100% portable)

"What should it profit a man, if he should win a flame war, yet lose his cool?"

Google "atomicity" and "race case" for more information, but here's a brief way how that would die: (P1 is process 1, P2 is process 2, they're not actually in the same program, but the commands from each are interleaved here since that can happen in reality)


P1: my $lflag = ( -l 'foo' ); # seems good
P2: makes foo a link - uh oh!
P1: $lflag or open my $fh, ">>foo"; # does it fine, since $lflag was s
+et before
P2: remove that link, lickity-split!
P1: $lflag = ( -l 'foo' ); # whups, everything *seems* ok...
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Make sense? Dave_the_m's code will exactly perform the actions for P2, btw. (Eimi's earlier explanation did exactly what your code does, too - look it over, the -l check happens before and after.)