in reply to PERL5LIB resets in a new terminal window
In a unix environment you can set environment variables in a set up file which gets run every time you open a new shell. The file name (.bashrc, .cshrc) varies depending on the shell you use.
I don't have a Mac, but googling 'mac environment' yeilds http://mactip.blogspot.com/2004/04/setting-environment-variables.html which mentions a .MacOSX/environment.plist file.
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