Revert 04746ad; this lets iread

inappropriately break up a multi-char input sequence.
Also make WIN32ungetch() push the char on the front of the queue
rather than the back.

os.c

@@ -183,7 +183,7 @@ public int iread(int fd, unsigned char *buf, unsigned int len)
 		c = getch();
 		if (c == '\003')
 			return (READ_INTR);
-		ungetcc_back(c);
+		ungetch(c);
 	}
 #endif
 #endif
@@ -264,7 +264,7 @@ public int iread(int fd, unsigned char *buf, unsigned int len)
 			reading = 0;
 			return (READ_INTR);
 		}
-		ungetcc_back(c);
+		WIN32ungetch(c);
 	}
 #endif
 #endif

screen.c

@@ -2824,6 +2824,17 @@ static void win32_unget_queue(char ch)
 	}
 }
 
+/*
+ * Make the next call to WIN32getch return ch.
+ */
+public void WIN32ungetch(int ch)
+{
+	WIN32_CHAR *wch = (WIN32_CHAR *) ecalloc(1, sizeof(WIN32_CHAR));
+	wch->wc_ch = ch;
+	wch->wc_next = win32_queue;
+	win32_queue = wch;
+}
+
 /*
  * Get a char from the front of the win32_queue.
  */
@@ -3041,14 +3052,6 @@ public char WIN32getch(void)
 	return (win32_get_queue());
 }
 
-/*
- * Make the next call to WIN32getch return ch.
- */
-public void WIN32ungetch(int ch)
-{
-	win32_unget_queue(ch);
-}
-
 public void win32_getch_clear(void)
 {
 	while (win32_kbhit())