fix typo, add explanatory comment

svn:r7026

src/or/dns.c

@@ -8,7 +8,7 @@ const char dns_c_id[] =
 /**
  * \file dns.c
  * \brief Implements a local cache for DNS results for Tor servers.
- * We provide two asynchrounous backend implementations:
+ * We provide two asynchronous backend implementations:
  *   1) A farm of 'DNS worker' threads or processes to perform DNS lookups for
  *      onion routers and cache the results.
  *   2) A wrapper around Adam Langley's eventdns.c code, to send requests

src/or/main.c

@@ -2143,7 +2143,7 @@ tor_main(int argc, char *argv[])
   case CMD_VERIFY_CONFIG:
     printf("Configuration was valid\n");
     break;
-  case CMD_RUN_UNITTESTS:
+  case CMD_RUN_UNITTESTS: /* only set by test.c */
   default:
     log_warn(LD_BUG,"Illegal command number %d: internal error.",
              get_options()->command);