The kitty keyboard protocol docs recommend CSI ? u to query support for
that protocol, see https://sw.kovidgoyal.net/kitty/keyboard-protocol/
For better or worse, fish shell uses this query to work around bugs
in other terminals triggered by requesting that protocol via CSI = 5 u.
Unfortunately, st interprets CSI ? u as DECRC (restore cursor
position). reproduce with 'printf "\x1b[?u"; cat'.
fish could work around this by switching to the alternate screen
before running this query; but that might cause tearing on terminals
that don't support Synchronized Output. I'm not sure.
In the meantime, let's correct our parser.
This adds a redundant else-after-return, for consistency with the
surrounding code.
---
st.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/st.c b/st.c
index 2e3800e..03b9bc8 100644
--- a/st.c
+++ b/st.c
@@ -1801,7 +1801,11 @@ csihandle(void)
tcursor(CURSOR_SAVE);
break;
case 'u': /* DECRC -- Restore cursor position (ANSI.SYS) */
- tcursor(CURSOR_LOAD);
+ if (csiescseq.priv) {
+ goto unknown;
+ } else {
+ tcursor(CURSOR_LOAD);
+ }
break;
case ' ':
switch (csiescseq.mode[1]) {
--
2.48.1
