Blocking Operations

The notion of blocking in a Windows environment has historically been a very important one. In Windows Sockets 1.1 environments, blocking calls were discouraged since they tend to disable ongoing interaction with the Windowing system, and since they employ a pseudo blocking technique which, for a variety of reasons, does not always work as intended. However, in preemptively scheduled Win32 environments such as Windows 95/98® and Windows NT®/Windows® 2000, blocking calls make much more sense, can be implemented by native operating system services, and are in fact a generally preferred mechanism. The Windows Sockets 2 API no longer supports psuedo blocking, but because the Windows Sockets 1.1 compatibility shims must continue to emulate this behavior, service providers must support this as described below.