Terminal Control (⎕ML)

⎕TC is a deprecated feature and is replaced by ⎕UCS (see note).

⎕TC is a simple three element vector. If ⎕ML<3 this is ordered as follows:

⎕TC[1]	Backspace
⎕TC[2]	Linefeed
⎕TC[3]	Newline

Note that ⎕TC≡⎕AV[1+⍳3] for ⎕ML<3 .

If ⎕ML≥3the order of the elements of ⎕TC is instead compatible with IBM's APL2:

⎕TC[1]	Backspace
⎕TC[2]	Newline
⎕TC[3]	Linefeed

Elements of ⎕TC beyond 3 are not defined but are reserved.

Note

With the introduction of ⎕UCS in Version 12.0, the use of ⎕TC is discouraged and it is strongly recommended that you generate control characters using ⎕UCS instead. This recommendation holds true even if you continue to use the Classic Edition.

Control Character	Old	New
Backspace	⎕TC[1]	⎕UCS 8
Linefeed	⎕TC[2] (⎕ML<3) ⎕TC[3] (⎕ML≥3)	⎕UCS 10
Newline	⎕TC[3] (⎕ML<3) ⎕TC[2] (⎕ML≥3)	⎕UCS 13