Hotfix: discard NUL characters in readline, rather than faking EOF on the console.

apps/system/readline/readline.c

@@ -126,7 +126,7 @@ static inline int readline_rawgetc(int infd)
    * error occurs).
    */
 
-  do
+  for (;;)
     {
       /* Read one character from the incoming stream */
 
@@ -154,14 +154,22 @@ static inline int readline_rawgetc(int infd)
             {
               return -errcode;
             }
-        }
-    }
-  while (nread < 1);
 
-  /* On success, return the character that was read */
+          continue;
+        }
+
+      else if (buffer == '\0')
+        { 
+          /* Ignore NUL characters, since they look like EOF to our caller */
+
+          continue;
+        }
+
+      /* Success, return the character that was read */
 
       return (int)buffer;
     }
+}
 
 /****************************************************************************
  * Name: readline_consoleputc