PORTEMUPortParams

This structure is used when creating a virtual COM port.

typedef struct _portemu_port_params {
  int channel;
  int flocal;
  BD_ADDR device;
  int imtu;
  int iminmtu;
  int imaxmtu;
  int isendquota;
  int irecvquota;
  GUID uuidService;
  unsigned int uiportflags;
} PORTEMUPortParams;

Members

• channel
  Set to either an explicit server channel, or, for a server application that wants the server channel to be autobound, to RFCOMM_CHANNEL_MULTIPLE.
• flocal
  Set to TRUE for a server port that accepts connections, or to FALSE for a client port that is used to creating outgoing connections.
• device
  The BD_ADDR of a target device on a client port.
• imtu
  The suggested number for the maximum transmission unit (MTU) for a packet in negotiations on connect, iminmtu and imaxmtu define acceptable range of negotiation (if all 3 are 0, default will be used).
• iminmtu
  Defines an acceptable range of negotiation.
• imaxmtu
  Defines an acceptable range of negotiation.
• isendquota
  Queue size on send. The WriteFile operation will block if isendquota is exceeded. If set to 0, the default setting is used.
• irecvquota
  Queue size on receive. Flow control is used to prevent receiving more data than irecvquota. Incoming data is discarded if it exceeds this limit. If set to 0, the default setting is used.
• uuidService
  Specifies the UUID for the target RFCOMM service. If channel == 0 for the client port, an SDP query is performed to determine the target channel id before the connection is made.
• uiportflags
  Can be a combination of the following flags.

  Flag	Hex code
  RFCOMM_PORT_FLAGS_REMOTE_DCB	0x00000001
  RFCOMM_PORT_FLAGS_KEEP_DCD	0x00000002
  RFCOMM_PORT_FLAGS_AUTHENTICATE	0x00000004
  RFCOMM_PORT_FLAGS_ENCRYPT	0x00000008

Remarks

If RFCOMM_PORT_FLAGS_AUTHENTICATE and/or RFCOMM_PORT_FLAGS_ENCRYPT is set, authentication is performed and/or encryption is toggled at connection establishment.

If RFCOMM_PORT_FLAGS_REMOTE_DCB is set, the Get or SetCommState functions initiate RFCOMM "remote port negotiation" (RPN) command, otherwise a local copy of DCB is being operated on.

If RFCOMM_PORT_FLAGS_KEEP_DCD, the data carrier detect flag is raised on connection and kept up throughout. In NULL-modem cable, DCD is paired with DSR signal and is always on. The direct connection UNIMODEM function uses DCD to detect cable unplugging. If a peer does not keep this bit on throughout the connection, this flag may be used to have port emulation layer simulate the bit being on.

Requirements

OS Versions: Windows CE .NET 4.0 and later.
Header: Bt_api.h.

See Also

BD_ADDR

Last updated on Wednesday, April 13, 2005

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