IO Variable

Material prepared from M Programming Book [WALTERS1997] (Pages 157,161) [WALTERS1997] and GT.M Programmer’s Guide

Input/Output Variable:

$I[O]

The I/O Variable is an intrinsic special variable, as seen by the ‘$’ prefix. The I/O Variable is a variable which designates the current I/O stream. This variable can be changed using the NEW Command and SET Command commands.

You can see the value of the I/O variable with the following code:

WRITE $IO

or the short form

W $I