When specified, the function call will use the application's current locale rather than forcing the use of neutral culture settings are omitted.
This flag is presently only supported in the following functions:
The functions listed above rely on certain standard C string manipulation and formatting routines. On POSIX-compatible platforms other than Windows and OS X, the application's locale must be set to the "POSIX" or "C" locale to function properly; however, this can have unexpected side-effects if your application uses vfork. To avoid conflicts while using vfork, you can specify this flag on any relevant functions, and manually set the locale for your application as appropriate. Note that this flag is not necessary to use on Windows or OS X.