CRT Conflict with Getservbyname

ID: Q177653

The information in this article applies to:

Microsoft Windows NT Workstation version 4.0
Microsoft Windows NT Server version 4.0
Microsoft Windows NT Server version 4.0, Terminal Server Edition

SYMPTOMS

When you use the getservbyname() function, an error is returned and the Services file located in %SystemRoot\System32\Drivers\Etc cannot be processed.

CAUSE

When C runtimes (CRTs) are linked dynamically (/MD - use Msvcrt.dll), the modules share one copy of the _fmode global variable. A change from its default _O_TEXT to _O_BINARY affects all modules, causing getservbyname to fail because it expects _O_TEXT.

When the CRT is linked statically, there are multiple copies of the CRT (and, therefore, multiple copies of _fmode) involved, meaning that changing the value of _fmode in the program changes the default mode for fopen throughout the .exe, but the default mode for any calls to fopen from the sockets DLL accesses the _fmode variable in CRT DLL whose value is _O_TEXT; therefore, no failure.

RESOLUTION

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or Windows NT Server 4.0, Terminal Server Edition. For additional information, please see the following article in the Microsoft Knowledge Base:

Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

Note that a specific version of this hotfix is now available for customers seeing this issue on Windows NT Terminal Server. Please contact Microsoft Customer support to obtain this fix.

STATUS

Microsoft has confirmed this to be a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition. This problem was first corrected in Windows NT 4.0 Service Pack 4.0 and Windows NT Server 4.0, Terminal Server Edition Service Pack 4.

Keywords : NT4SP4Fix kbbug4.00 ntprotocol kbfix4.00.sp4 NTSrvWkst
Version : WinNT:4.0
Platform : winnt
Issue type : kbbug