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This rule finds global variables which have a name of length three characters or less. It is particularly important to use descriptive names for global variables. Use of a clear naming convention for global variables helps document their use, avoids pollution of the namespace and reduces the risk of shadowing with local variables.
Review the purpose of the each global variable flagged by this rule and update each name to reflect the purpose of the variable.
Mats Henricson and Erik Nyquist, Industrial Strength C++, published by Prentice Hall PTR (1997). Chapter 1: Naming, Rec 1.1 (PDF).