TCP Read

Reads a number of bytes from a TCP network connection, returning the results in data out.

mode indicates the behavior of the read operation.

1Standard (default)—Waits until all bytes requested have arrived or until the time runs out. Returns the number of bytes that have been received so far. If less than the requested number of bytes arrives, reports a timeout error.
2Buffered—Waits until all bytes requested have arrived or until the time runs out. Returns the number of bytes requested or none. If less than the requested number of bytes arrive, reports a timeout error.
3CRLF—Waits until a CR (carriage return) followed by a LF (line feed) are received within the number of bytes requested or until the time runs out. Returns the bytes received up to and including the CR and LF or none. If a CR and LF are not found, reports a timeout error.
4Immediate—Waits until any bytes are received. Waits the full timeout only if no bytes have been received. Returns the number of bytes received so far. Reports a timeout error if no bytes have been received.
connection ID is a network connection refnum that uniquely identifies the TCP connection you want to close.
bytes to read is the number of bytes to read.
timeout ms is in milliseconds. If the connection is not established in the specified time, the VI completes and returns an error. The default is –1, which indicates to wait indefinitely.
error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurs before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.
status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
code is the error or warning code. The default is 0. If status is TRUE, code is a non-zero error code. If status is FALSE, code is 0 or a warning code.
source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
connection ID out has the same value as connection ID.
data out contains the data read from the TCP connection.
error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out indicator on the front panel and select Explain Error from the shortcut menu for more information about the error.
status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
code is the error or warning code. If status is TRUE, code is a non-zero error code. If status is FALSE, code is 0 or a warning code.
source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.