WinSock Zero-Length Packet Not Sent on Network

• Microsoft Windows 95

SYMPTOMS

In Windows 95, if the Windows Sockets Send() function is used to send zero-length packets using a stream-oriented socket over IPX/SPX, the function returns a success status, but no packet is sent on the network.

CAUSE

The WinSock specifications do not require that a Send() function with a length of zero actually result in a packet being sent over the network when the Send() function is called on a stream-oriented socket. Windows 95 does not actually send a packet across the network when the Send() function is called with a length of zero over a stream-oriented socket over SPX/IPX.

STATUS

Microsoft has confirmed this to be a limitation of Microsoft Windows 95. An update to address this limitation is in development, but has not been regression tested and may be destabilizing in production environments. Microsoft does not recommend implementing this update at this time. Contact Microsoft Technical Support for more information about the availability of this update.

MORE INFORMATION

According to the WinSock 2.0 specification, calling the Send() function with a length of zero is to be treated by implementations as successful. In this case, the Send() function may return 0 as a valid return value. For message-oriented sockets, a zero-length transport datagram is sent.