Edit

TRANSMIT_PACKETS_ELEMENT structure (mswsock.h)

  • Article

The TRANSMIT_PACKETS_ELEMENT structure specifies a single data element to be transmitted by the TransmitPackets function.

Syntax

typedef struct _TRANSMIT_PACKETS_ELEMENT {
  ULONG dwElFlags;
  ULONG cLength;
  union {
    struct {
      LARGE_INTEGER nFileOffset;
      HANDLE        hFile;
    };
    PVOID pBuffer;
  };
} TRANSMIT_PACKETS_ELEMENT, *PTRANSMIT_PACKETS_ELEMENT, *LPTRANSMIT_PACKETS_ELEMENT;

Members

dwElFlags

Type: ULONG

Flags used to describe the contents of the packet array element, and to customize TransmitPackets function processing. The following table lists valid flags:

Flag Meaning
TP_ELEMENT_FILE
 Specifies that data resides in a file. Default setting for dwElFlags. Mutually exclusive with TP_ELEMENT_MEMORY.
TP_ELEMENT_MEMORY
 Specifies that data resides in memory. Mutually exclusive with TP_ELEMENT_FILE.
TP_ELEMENT_EOP
 Specifies that this element should not be combined with the next element in a single send request from the sockets layer to the transport. This flag is used for granular control of the content of each message on a datagram or message-oriented socket.

cLength

Type: ULONG

The number of bytes to transmit. If zero, the entire file is transmitted.

nFileOffset

Type: LARGE_INTEGER

The file offset, in bytes, at which to begin the transfer. Valid only if TP_ELEMENT_FILE is specified in dwEIFlags. When set to –1, transmission begins at the current byte offset.

hFile

Type: HANDLE

A handle to an open file to be transmitted. Valid only if TP_ELEMENT_FILE is specified in dwEIFlags. Windows reads the file sequentially; caching performance is improved by opening this handle with FILE_FLAG_SEQUENTIAL_SCAN.

pBuffer

Type: PVOID

A pointer to the data in memory to be sent. Valid only if TP_ELEMENT_MEMORY is specified in dwEIFlags.

Requirements

Requirement Value
Minimum supported client Windows XP [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Header mswsock.h

See also

TransmitPackets

LPFN_WSARECVMSG (WSARecvMsg)

send