Using glob() is the best solution, since it doesn't include . and .. in the solution set. But, in general, if there are things you want to skip over, I find the NEXT statement with conditional modifier is the clearest solution:

foreach ( readdir PRINT ) {
   next if ( ( $_ eq '.' ) or ( $_ eq '..' ) );
# or, alternately ...
   next if /^..?$/;
}
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The first line is explicitly clear and is fast. Regex cannot be faster than straightfoward string comparison, but in this case the small number of characters and the idiomatic nature makes the code clear to undnerstand.