Thanks for the clarification about the way the reference is used. The code I supplied is an example and in reality %hash would be the result of another sub call, so I can't pass by value. As I need to then call other subs with \%hash as an argument (some of which need to modify %hash), I'll need to find another way.

In reply to Re^2: Global variable unexpectedly modified when passed by reference by fshrewsb
in thread Global variable unexpectedly modified when passed by reference by fshrewsb

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