Commit: patch 9.2.0389: DECRQM still leaves stray "pp" on Apple Terminal.app

[Christian Brabandt]

patch 9.2.0389: DECRQM still leaves stray "pp" on Apple Terminal.app

Commit: https://github.com/vim/vim/commit/44f707da6a06b8310bfe23f5477c7653215e1230
Author: Hirohito Higashi <h.eas...@gmail.com>
Date: Wed Apr 22 20:22:25 2026 +0000

patch 9.2.0389: DECRQM still leaves stray "pp" on Apple Terminal.app

Problem: DECRQM was still sent to Apple Terminal.app before its DA2
reply was processed, leaving a literal "pp" on screen.
may_req_decrqm() was called from vim_main2()
right after may_req_termresponse(), at which point
term_props[TPR_DECRQM].tpr_status was still TPR_UNKNOWN, so
the `!= TPR_NO` guard let the request through (after v9.2.0387)
Solution: Send DECRQM from handle_version_response() once
term_props[TPR_DECRQM].tpr_status == TPR_YES, the same
pattern already used for t_RS (TPR_CURSOR_STYLE) and t_RC
(TPR_CURSOR_BLINK), which deliberately wait for the DA2
reply to avoid the same echo-on-screen issue on Apple
Terminal.app and Gnome terminal. Drop the now-unused
may_req_decrqm() helper and its call site in vim_main2()
(Hirohito Higashi).

fixes: #19852
related: #19938
closes: #20038

Co-Authored-By: Claude Opus 4.7 (1M context) <nor...@anthropic.com>
Co-Authored-By: John Marriott <basi...@internode.on.net>
Signed-off-by: Hirohito Higashi <h.eas...@gmail.com>
Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/src/main.c b/src/main.c
index e0d0e7e37..cac5db145 100644
--- a/src/main.c
+++ b/src/main.c
@@ -892,10 +892,6 @@ vim_main2(void)
may_req_termresponse();

may_req_bg_color();
-
- // Same reason as for termresponse: don't want the terminal sending out
- // the DECRPM response after Vim has exited.
- may_req_decrqm();
# endif

// start in insert mode
diff --git a/src/proto/term.pro b/src/proto/term.pro
index 5ec909f46..9653a35af 100644
--- a/src/proto/term.pro
+++ b/src/proto/term.pro
@@ -60,7 +60,6 @@ void stoptermcap(void);
void may_req_termresponse(void);
void check_terminal_behavior(void);
void may_req_bg_color(void);
-void may_req_decrqm(void);
int swapping_screen(void);
void scroll_start(void);
void cursor_on_force(void);
diff --git a/src/term.c b/src/term.c
index 876e15d95..07eb5974b 100644
--- a/src/term.c
+++ b/src/term.c
@@ -690,15 +690,17 @@ static tcap_entry_T builtin_sync_output[] = {
};
#endif

+#ifdef FEAT_TERMRESPONSE
/*
* List of DECRQM modes that Vim supports
*/
static const int dec_modes[] = {
2026, // Synchronized output
-#ifdef UNIX
+# ifdef UNIX
2048 // In-band terminal resize events
-#endif
+# endif
};
+#endif

#ifdef FEAT_TERMGUICOLORS
/*
@@ -4312,36 +4314,6 @@ may_req_bg_color(void)
}
}

-/*
- * Query the settings for the DEC modes we support via DECRQM.
- * Only sent once, and only when the terminal is known not to dislike it
- * (i.e. TPR_DECRQM is TPR_YES, or still TPR_UNKNOWN when the version response
- * has not yet been received).
- * The DECRPM responses are caught in handle_csi().
- */
- void
-may_req_decrqm(void)
-{
- if (decrqm_status.tr_progress == STATUS_GET
- && term_props[TPR_DECRQM].tpr_status != TPR_NO
- && can_get_termresponse()
- && starting == 0)
- {
- MAY_WANT_TO_LOG_THIS;
- LOG_TR1("Sending DECRQM requests");
- for (int i = 0; i < (int)ARRAY_LENGTH(dec_modes); i++)
- {
- vim_snprintf((char *)IObuff, IOSIZE, " [?%d$p", dec_modes[i]);
- out_str(IObuff);
- }
- termrequest_sent(&decrqm_status);
- // check for the characters now, otherwise they might be eaten by
- // get_keystroke()
- out_flush();
- (void)vpeekc_nomap();
- }
-}
-
#endif

/*
@@ -5398,6 +5370,23 @@ handle_version_response(int first, int *arg, int argc, char_u *tp)
need_flush = TRUE;
}

+ // Only request DEC modes via DECRQM when the terminal is known to
+ // handle it. Not for Apple Terminal.app or GNU screen, they echo
+ // the trailing "p" to the screen. See issue #19852.
+ if (decrqm_status.tr_progress == STATUS_GET
+ && term_props[TPR_DECRQM].tpr_status == TPR_YES)
+ {
+ MAY_WANT_TO_LOG_THIS;
+ LOG_TR1("Sending DECRQM requests");
+ for (int i = 0; i < (int)ARRAY_LENGTH(dec_modes); i++)
+ {
+ vim_snprintf((char *)IObuff, IOSIZE, " [?%d$p", dec_modes[i]);
+ out_str(IObuff);
+ }
+ termrequest_sent(&decrqm_status);
+ need_flush = TRUE;
+ }
+
if (need_flush)
out_flush();
#endif
diff --git a/src/version.c b/src/version.c
index 95f20bc67..bfd90a13f 100644
--- a/src/version.c
+++ b/src/version.c
@@ -729,6 +729,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 389,
/**/
388,
/**/