All C and C++ applications using locales of type *LOCALE have an active locale which is scoped to the activation group of the program. The active locale determines the behavior of the locale-sensitive functions in the C library. The active locale can be set explicitly with a call to setlocale(). See the ILE C/C++ Run-Time Library Functions for more information on using setlocale().
If the active locale is not set explicitly by a call to setlocale(), it is implicitly set by the C run-time environment at program activation time. Here is how the run-time environment sets the active locale when a program is activated:
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