5. Defines

SDL_NET_MAJOR_VERSION

1
SDL_net library major number at compilation time

SDL_NET_MINOR_VERSION

2
SDL_net library minor number at compilation time

SDL_NET_PATCHLEVEL

7
SDL_net library patch level at compilation time

INADDR_ANY

0x00000000 (0.0.0.0)
used for listening on all network interfaces.

INADDR_NONE

0xFFFFFFFF (255.255.255.255)
which has limited applications.

INADDR_BROADCAST

0xFFFFFFFF (255.255.255.255)
used as destination when sending a message to all clients on a subnet that allows broadcasts.

SDLNET_MAX_UDPCHANNELS

32
The maximum number of channels on a UDP socket.

SDLNET_MAX_UDPADDRESSES

4
The maximum number of addresses bound to a single UDP socket channel