MessagePacket (Built-in Mathematica Symbol)

MessagePacket[symbol, string] is a MathLink packet containing a Mathematica message identifier of the form symbol::string.

InputPacket (Built-in Mathematica Symbol)

InputPacket[] is a MathLink packet that indicates a prompt for input as generated by Input.

InputStringPacket (Built-in Mathematica Symbol)

InputStringPacket[] is a MathLink packet that requests input in string form.

Using MathLink to Communicate between ... (Mathematica Tutorial)

MathLink connections between Mathematica sessions. This starts up a link on port number 8000. This connects to the link on port 8000.

DisplayEndPacket (Built-in Mathematica Symbol)

DisplayEndPacket[] is a MathLink packet that indicates the end of a series of expressions relating to a postscript graphic.

DisplayPacket (Built-in Mathematica Symbol)

DisplayPacket[] is a MathLink packet that indicates the beginning of a series of expressions related to a PostScript graphic.

SyntaxPacket (Built-in Mathematica Symbol)

SyntaxPacket[integer] is a MathLink packet where integer indicates the position at which a syntax error was detected in the input line.

LinkInterrupt (Built-in Mathematica Symbol)

LinkInterrupt[link] sends an interrupt to the program at the other end of the specified MathLink connection.

ReturnExpressionPacket (Built-in Mathematica Symbol)

ReturnExpressionPacket[expr] is a MathLink packet that contains the expression expr, the result of an EnterExpressionPacket evaluation.

BeginDialogPacket (Built-in Mathematica Symbol)

BeginDialogPacket[integer] is a MathLink packet that indicates the start of the Dialog subsession referenced by integer.