I think that the following would achieve what you require: 
if ("true" eq $flag) {
    open (OUT, ">output.txt") or die ("could not open output.txt: $!")
+;
} else {
    open (OUT, ">&STDOUT");
}

[download]

Update:Changed as per bbfu's comment below, although I kept the duplication because IMHO it makes it easier for a newbie to follow.

*~-}hotyopa{-~*

In reply to Re: can you assign file handles? by hotyopa
in thread can you assign file handles? by Anonymous Monk

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