Ns_SetSockErrno(int err);
This function (along with the other error reporting functions listed below) is part of a platform-independent interface to the error reporting mechanisms on Unix and NT. On Unix, the per-thread errno variable is used, and on Windows NT, the standard GetLastError() and SetLastError() mechanism is used. The nssocket.h header defines the Windows NT style error names to equal the Unix style error names for the most common error numbers.