BUG: Windows 95/98 Do Not Allow open_osfhandle on Socket Handles

ID: Q139801

The information in this article applies to:

Microsoft Win32 Software Development Kit (SDK)
on the following platforms: Win95, Win98
Microsoft Visual C++, 32-bit Editions, versions 4.0, 5.0

SYMPTOMS

The Visual C++ run-time API _open_osfhandle on Windows 95 and Windows 98 fails when called with a socket handle as the argument. The call returns -1 with errno set to EINVAL.

CAUSE

The _open_osfhandle API makes a call to GetFileType to verify the handle type. Under Windows 95 and Windows 98, GetFileType returns FILE_TYPE_UNKNOWN for a socket handle instead of FILE_TYPE_PIPE. The _open_osfhandle API does not convert handles of unknown type.

STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article.

MORE INFORMATION

Applications on Windows NT may use _open_osfhandle to get a C run-time file descriptor from a Windows NT socket handle. This enables the application to use the descriptor in C run-time I/O operations such as _lread() and so on.

Windows 95 and Windows 98 do not allow this operation.

Additional query words:


Keywords          : kbnetwork kbAPI kbSDKPlatform kbVC400bug kbVC500bug kbWinOS95bug kbWinsock kbGrpNet 
Version           : WINDOWS:; winnt:4.0,5.0
Platform          : WINDOWS winnt 
Issue type        : kbbug

Last Reviewed: June 24, 1999