I'm developing a module which, among other things: opens, selects, and keeps track of output file handles. A user can call: openOut(*OUT,$outputFile) and the handle is auto-selected so that prints without file handles go to the opened output file. There's also a corresponding closeOut(*OUT), but I don't want to force the user to call it. Hence, when I use the module, I will see: 
Runtime warning: [Name "main::OUT" used only once: possible typo at no
+close_test.pl line 50.].

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I was reading up on this warning and saw that somehow the sort builtin manages to suppress these warnings regarding $a and $b. That's what I'd like to do, but for whatever file handle the user decides to use in the call to my openOut method. Can I do that from my module without forcing the user to add any extra code?

I know I can catch these warnings with a SIG{__WARN__}, but I don't want to suppress good warnings or add detail to an unrelated warning about suggesting a call to closeOut.

In reply to How to suppress "only used once" regarding script file handles (that are in fact used in my module), but do it from a the module? by hepcat72

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