ERM Erasure Mode
Whether erasing touches protected areas.
CSI 6 h/l
- ECMA-48
- §7.2.4 ERM – Erasure Mode, p. 22
Mode 6 decides whether the erasing functions, ED, EL, ECH, EA and EF, erase the characters in protected areas as well. In ECMA-48 an area is protected with SPA and EPA, or with DAQ.
| State | ECMA-48 calls it | Meaning |
|---|---|---|
Reset, CSI 6 l | PROTECT | only unprotected areas are erased |
Set, CSI 6 h | ALL | protected areas are erased as well |
DEC STD 070 does not list it, and does not need it: a DEC terminal’s protection is DECSCA, which only the selective erases, DECSED and DECSEL, honor.
Neither xterm nor libghostty-vt implements it. Both ignore CSI 6 h and CSI 6 l, and both answer DECRQM with 0, not recognized: the mode is not among the ones xterm’s do_ansi_rqm answers for.
Support
| Terminal | Version | Support | Notes |
|---|---|---|---|
| VT220 | manual, 2nd ed., 1984 | No | not in the manual, whose table of ANSI modes has only KAM, IRM, SRM and LNM |
| VT510 | manual, 1st ed., 1993 | No | not in the manual |
| xterm | patch 412, xterm-411a | No | ignored; DECRQM answers 0 |
| libghostty-vt | 0f171f6 | No | ignored; DECRQM answers 0 |
| ConEmu | build 230724, its documentation | No | not in its ANSI escape codes |
Validation
ERM-1: Not recognized
\e[6$p
|_____|
reply \e[6;0$y
ERM-2: Not recognized after it is set, either
\e[6h
\e[6$p
|_____|
reply \e[6;0$y