libedit: Try to map <Delete> to ed-delete-next-char.

This adds a new "arrow" key "delete" corresponding to the kD termcap value.
It only works if that is a sequence such as "\033[3~"; if it is "\177", the
em-delete-prev-char or ed-delete-prev-char from the single-character
mappings remains. It turns out that most terminals (xterm and alikes,
syscons in xterm mode) produce "\033[3~" by default so <Delete> has the
expected effect.

This also means that things need to be considerably misconfigured for
<Backspace> to perform a <Delete> action.

2 files changed, 10 insertions, 2 deletions

diff --git a/lib/libedit/term.c b/lib/libedit/term.c
index cffad07..1d89279 100644
--- a/lib/libedit/term.c
+++ b/lib/libedit/term.c
@@ -223,7 +223,9 @@ private const struct termcapstr {
 	{ "kh", "send cursor home" },
 #define	T_at7	37
 	{ "@7", "send cursor end" },
-#define	T_str	38
+#define	T_kD	38
+	{ "kD", "send cursor delete" },
+#define	T_str	39
 	{ NULL, NULL }
 };
 
@@ -1062,6 +1064,11 @@ term_init_arrow(EditLine *el)
 	arrow[A_K_EN].key = T_at7;
 	arrow[A_K_EN].fun.cmd = ED_MOVE_TO_END;
 	arrow[A_K_EN].type = XK_CMD;
+
+	arrow[A_K_DE].name = "delete";
+	arrow[A_K_DE].key = T_kD;
+	arrow[A_K_DE].fun.cmd = ED_DELETE_NEXT_CHAR;
+	arrow[A_K_DE].type = XK_CMD;
 }
 
 
diff --git a/lib/libedit/term.h b/lib/libedit/term.h
index 8ded5d7..15d393c 100644
--- a/lib/libedit/term.h
+++ b/lib/libedit/term.h
@@ -79,7 +79,8 @@ typedef struct {
 #define	A_K_RT		3
 #define	A_K_HO		4
 #define	A_K_EN		5
-#define	A_K_NKEYS	6
+#define	A_K_DE		6
+#define	A_K_NKEYS	7
 
 protected void	term_move_to_line(EditLine *, int);
 protected void	term_move_to_char(EditLine *, int);