Intel Extensible Firmware Interface - Manual (Page 628)

Extensible Firmware Interface Specification
15-22 12/01/02 Version 1.10
EFI_SIMPLE_NETWORK.Transmit()
Summary
Places a packet in the transmit queue of a network interface.
Prototype
EFI_STATUS
(EFIAPI *EFI_SIMPLE_NETWORK_TRANSMIT) (
IN EFI_SIMPLE_NETWORK *This
IN UINTN HeaderSize,
IN UINTN BufferSize,
IN VOID *Buffer,
IN EFI_MAC_ADDRESS *SrcAddr OPTIONAL,
IN EFI_MAC_ADDRESS *DestAddr OPTIONAL,
IN UINT16 *Protocol OPTIONAL,
);
Parameters
This A pointer to the EFI_SIMPLE_NETWORK instance.
HeaderSize The size, in bytes, of the media header to be filled in by the
Transmit() function. If HeaderSize is nonzero, then it
must be equal to This->Mode->MediaHeaderSize and
the DestAddr and Protocol parameters must not be NULL .
BufferSize The size, in bytes, of the entire packet (media header and data) to
be transmitted through the network interface.
Buffer A pointer to the packet (media header followed by data) to be
transmitted. This parameter cannot be
NULL . If HeaderSize
is zero, then the media header in Buffer must already be filled
in by the caller. If HeaderSize is nonzero, then the media
header will be filled in by the Transmit() function.
SrcAddr The source HW MAC address. If HeaderSize is zero, then
this parameter is ignored. If HeaderSize is nonzero and
SrcAddr is NULL , then This->Mode->CurrentAddress
is used for the source HW MAC address.
DestAddr The destination HW MAC address. If HeaderSize is zero,
then this parameter is ignored.
Protocol The type of header to build. If HeaderSize is zero, then this
parameter is ignored. See RFC 1700, section “Ether Types,”
for examples.