Table Of Contents
TCP Read (TCP Read Text) (G Dataflow)
Reads a number of bytes from a TCP network connection and returns the results as string data.
Programming Patterns
mode
The behavior of the read operation.
This input determines the following aspects of this node's behavior:
- The condition(s) that must be met before this node returns data
- The kind of data that this node returns
| Name | Description |
|---|---|
| Standard | Waits until all bytes to read arrive or until this node times out before returning data. This node returns the number of bytes read so far. If fewer bytes than the number you requested arrive, this node returns the partial number of bytes and reports a timeout error. |
| Buffered | Waits until all bytes to read arrive or until this node times out before this node returns data. If fewer bytes than the number you requested arrive, this node returns no bytes and reports a timeout error. |
| CRLF | Waits until all bytes to read arrive, until this node receives a carriage return (CR) followed by a linefeed (LF) within the number of bytes to read, or until this node times out before this node returns data. This node returns the bytes up to and including the CR and LF if it finds them in the bytes to read. |
| Immediate | Returns data as soon as this node receives any bytes to read. This node waits the full timeout only if it receives no bytes to read. This node returns the number of bytes received so far and reports a timeout error only if this node receives no bytes. |
Default: Standard
connection ID in
A network connection refnum that uniquely identifies the TCP connection.
Use TCP Open Connection to generate a refnum to wire to this input.
bytes to read
The number of bytes this node reads.
Wire a value greater than 0 to this input to read data.
Default: 0
timeout ms
Time, in milliseconds, that the node waits to complete before reporting a timeout error.
Wire a -1 to this input to wait indefinitely.
Default: 25,000 ms
error in
Error conditions that occur before this node runs.
The node responds to this input according to standard error behavior.
Standard Error Behavior
Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.
Default: No error
connection ID out
Same value as connection ID in.
error out
This node can return the following error codes.
| 56 | The network operation exceeded the user-specified or system time limit. |
| 62 | The system caused the network connection to be aborted. |
| 64 | The network connection is not yet established. |
| 66 | The network operation was closed by the peer. |
Standard Error Behavior
Many nodes provide an error in input and an error out output so that the node can respond to and communicate errors that occur while code is running. The value of error in specifies whether an error occurred before the node runs. Most nodes respond to values of error in in a standard, predictable way.
Where This Node Can Run:
Desktop OS: Windows
FPGA: Not supported
Web Server: Not supported in VIs that run in a web application