From 94fb742a93db0c57b0f2cb42c04d55df425d4286 Mon Sep 17 00:00:00 2001
From: June McEnroe <june@causal.agency>
Date: Mon, 9 Mar 2020 19:27:15 -0400
Subject: Add \? exit status prompt expansion

---
 bin/1sh/1sh.1    |  2 ++
 bin/1sh/parser.c | 12 ++++++++++++
 2 files changed, 14 insertions(+)

(limited to 'bin')

diff --git a/bin/1sh/1sh.1 b/bin/1sh/1sh.1
index 9bbd881b..d72a87c7 100644
--- a/bin/1sh/1sh.1
+++ b/bin/1sh/1sh.1
@@ -1427,6 +1427,8 @@ This system's hostname.
 The final component of the current working directory.
 .It Li \ew
 The entire path of the current working directory.
+.It Li \e?
+Exit status if it is non-zero, empty string otherwise.
 .It Li \e$
 Superuser status.
 .Dq Li "$ "
diff --git a/bin/1sh/parser.c b/bin/1sh/parser.c
index 3f73220f..1038aa43 100644
--- a/bin/1sh/parser.c
+++ b/bin/1sh/parser.c
@@ -2038,6 +2038,18 @@ expandprompt(const char *fmt) {
 				--i;
 				break;
 
+				/*
+				 * Exit status if non-zero.
+				 */
+			case '?':
+				if (exitstatus != 0) {
+					snprintf(&ps[i], PROMPTLEN - i, "%d", exitstatus);
+					while (ps[i] != '\0')
+						i++;
+				}
+				i--;
+				break;
+
 				/*
 				 * Superuser status.
 				 *
-- 
cgit 1.4.1