PRB: setlocale(LC_ALL, ".OCP") Returns NULL for Some Locales on US Windows NT 4.0 (230138)

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256986 Description of the Microsoft Windows Registry

SYMPTOMS

On Windows NT 4.0, if the locale is similar to one of the following, setlocale(LC_ALL,".OCP") may return NULL:

Russian_Russia
Serbian (Latin)_Serbia
Slovak_Slovakia
Turkish_Turkey
Ukrainian_Ukraine

CAUSE

This is by design. Windows NT 4.0 no longer copies various OEM code pages to the system at installation time. For US Windows NT, only OEM code pages 437 and 850 are installed at setup time. The locales listed in the "Summary" section all require OEM code pages other than 437 and 850, and therefore setlocale(LC_ALL, ".OCP") returns NULL.

RESOLUTION

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To install the additional OEM code pages, copy them from the Windows NT setup CD to the Windows NT System32 directory, then update the registry:

HKEY_LOCAL_MACHINE\SYSTEM\currentcontrolset\control\NLS\codepage

The locale listed in the "Summary" section require different code pages:

Russian_Russia.866
Serbian (Latin)_Serbia.852
Slovak_Slovakia.852
Ukrainian_Ukraine.866