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TERM$
System variable: TERM$
Length: 3
Description:
The system variable named TERM$ contains the identification number of the terminal for the current program.
This value is a three-byte string in the form "Tnn", where "nn" is a value from "00" to "99".
When a program is running in a foreground partition, the value of TERM$ is identical to ITERM$.
However, for a program running in a background partition, TERM$ will contain a null value and ITERM$ will contain
the identification number of the terminal initiating the background process.
