RtnFrameAllocate

RtnFrameAllocate can be used by a filter driver, and an RTSS application with RT-TCP/IP support enabled, to allocate a block of memory to store an Ethernet frame. The length of the frame is guaranteed to be long enough to contain ulDataSize bytes of data plus 14 bytes for the Ethernet header. RtnFrameAllocate pre-populates the source Ethernet address of the device name passed.

NOTE: Frames must be released by calling RtnFrameFree API.

Syntax

VOID* RtnFrameAllocate(
   CHAR *DevName,
   ULONG ulDataSize
);

Parameters

Devname

Zero terminated string indicating which device to allocate a frame from.

ulDataSize

Size of the Ethernet payload data. This size does not include the 14 byte Ethernet header.

Return Value

A pointer to the Ethernet frame header of newly created frame if the function succeeds. NULL if the function fails.

Requirements

Minimum Supported Version	RTX64 4.0
Header	RtnApi.h
Library	RtTcpip.lib