The niladic system function ŒTC returns a three-element vector containing the three control characters: backspace, carriage return and linefeed. This is compatible with IBM's APL2 equivalent.
In addition, to assist migration of APL code from APL*Plus, APLX also
supports the following niladic system functions which return specific 'terminal-control'
characters as scalars:
ŒTCBEL Bell character, equivalent to ŒC[ŒIO+7] ŒTCBS Backspace, equivalent to ŒB or ŒTC[ŒIO+0] ŒTCDEL Delete character, equivalent to ŒC[ŒIO+32] ŒTCESC Escape character, equivalent to ŒC[ŒIO+27] ŒTCHT Horizontal tab character, equivalent to ŒT or ŒC[ŒIO+9] ŒTCFF Formfeed character, equivalent to ŒC[ŒIO+12] ŒTCHT Horizontal tab character, equivalent to ŒT or ŒC[ŒIO+9] ŒTCLF Linefeed character, equivalent to ŒL or ŒTC[ŒIO+2] ŒTCNL Newline (carriage return) character, equivalent to ŒR or ŒTC[ŒIO+1] ŒTCNUL Null character, equivalent to ŒAV[ŒIO+0]