Get protocol-specific service information. This subroutine enables a transport user to access this information during any phase of communication.
Parameters fd Specifies the file descriptor.
The transport provider supports a connection-mode service but does not support the optional orderly release facility. The transport provider supports a connection-mode service with the optional orderly release facility. The transport provider supports a connectionless-mode service. This is a bit field used to specify other information about the transport provider. If a transport user is concerned with protocol independence, the above sizes may be accessed to determine how large the buffers must be to hold each piece of information.