DSRequestMsg

Request message structure.

Synopsis

typedef struct DSRequestMsg {
 DS_MSG_HEADER

union {
 struct {
  DSDataType dataType;
  Item subscriberPort;
  } subscribe;

 struct {
  DSDataType exemptStream;
  unsigned long nowTime;
  } clockSync;

 struct {
  unsigned long markerValue;
  unsigned long options;
  } goMarker;

 struct {
  DSDataType streamType;
  long channelNumber;
  long* channelStatusPtr;
  } getChannel;

 struct {
  DSDataType streamType;
  long channelNumber;
  long channelStatus;
  } setChannel;

 struct {
  DSDataType streamType;
  long userDefinedOpcode;
  void* userDefinedArgPtr;
  } control;

 struct {
  Item acquirePort;
  } connect;

 struct {
  unsigned long options;
  } start;

 struct {
  unsigned long options;
  } stop;

 } msg;

} DSRequestMsg, *DSRequestMsgPtr

Description

Messages sent to the streamer by the application to control stream flow and parameters.

Fields

dataType: 4 byte ASCII data type identifier.

subscriberPort: Message port to send data to.

clockSync

exemptStream: Stream that sync message should not be sent to.

nowTime: Time value to propagate to everyone.

goMarker

markerValue: Place to "branch" to in the stream.

options: Options for branching.

getChannel

streamType: Which subscriber.

channelNumber: Logical data channel.

channelStatusPtr: Place to return channel status.

setChannel

streamType: Which subscriber.

channelNumber: Logical data channel.

channelStatus: Channel status bits to set.

Control

streamType: Subscriber to send control message to.

userDefinedOpcode: Subscriber defined action code.

userDefinedArgPtr: Subscriber defined argument.

connect

acquirePort: Connect this data port to stream.

start

options: Start options.

stop

options: Stop options.

Associated Files

DataStream.h