Index: bin/sh/parser.c
===================================================================
--- bin/sh/parser.c
+++ bin/sh/parser.c
@@ -45,6 +45,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <stdio.h>
+#include <time.h>
 
 #include "shell.h"
 #include "parser.h"
@@ -2088,6 +2089,60 @@
 					ps[i] = '\\';
 				break;
 
+			/*
+			 * Print time or date as per provided format.
+			 */
+		case 'D': {
+				char tfmt[128], *len;
+				time_t now;
+
+				if (fmt[1] != '{') {
+					/*
+					 * "\D" but not "\D{", so treat the
+					 * '\' literally and rewind fmt to
+					 * treat 'D' literally next iteration.
+					 */
+					ps[i] = '\\';
+					fmt--;
+					break;
+				}
+				/*
+				 * Consume the 'D' character and try to copy
+				 * fmt from after '{' until '}'.
+				 * Don't consume '{' from fmt yet.
+				 */
+				fmt++;
+				len = memccpy(tfmt, fmt + 1, '}', sizeof(tfmt));
+				if (len == NULL) {
+					/*
+					 * Format too long or '}' not found,
+					 * so ignore "\D{" altogether.
+					 * The loop will do i++, but nothing
+					 * was written to ps, so do i-- here.
+					 * "fmt++" will consume the '{'.
+					 */
+					i--;
+					break;
+				}
+				/*
+				 * Either way, consume fmt until '}'. The loop
+				 * will do fmt++ to finally consume the '}'.
+				 */
+				if (len - tfmt == 1) {
+					/* "\D{}" is documented to mean %X. */
+					fmt++;
+					strcpy(tfmt, "%X");
+				} else {
+					fmt += len - tfmt;
+					/* Truncate tfmt before '}'. */
+					*--len = '\0';
+				}
+				now = time(NULL);
+				i += strftime(&ps[i], PROMPTLEN - i - 1,
+					tfmt, localtime(&now)) - 1;
+			}
+			break;
+
 				/*
 				 * CRLF sequence
 				 */
Index: bin/sh/sh.1
===================================================================
--- bin/sh/sh.1
+++ bin/sh/sh.1
@@ -1428,6 +1428,18 @@
 may include any of the following formatting sequences,
 which are replaced by the given information:
 .Bl -tag -width indent
+.It Li \eD{format}
+The result of calling
+.Xr strftime 3
+with the provided
+.Ar format .
+and the current time.
+The braces are required.
+Empty
+.Ar format
+is equivalent to
+\&%X,
+national representation of the time.
 .It Li \eH
 This system's fully-qualified hostname (FQDN).
 .It Li \eh