diff --git a/src/app/main/main.c b/src/app/main/main.c
index 4275a98bd0..2a5cb4aa07 100644
--- a/src/app/main/main.c
+++ b/src/app/main/main.c
@@ -1279,6 +1279,13 @@ tor_run_main(const tor_main_configuration_t *tor_cfg)
 #endif
   }
 
+  if (tor_cfg->run_tor_only && get_options()->command != CMD_RUN_TOR) {
+    log_err(LD_CONFIG, "Unsupported command when running as an NT service.");
+    result = -1;
+    tor_cleanup();
+    goto done;
+  }
+
   switch (get_options()->command) {
   case CMD_RUN_TOR:
 #ifdef NT_SERVICE
diff --git a/src/app/main/ntmain.c b/src/app/main/ntmain.c
index a49dfdbbc9..3d923edf57 100644
--- a/src/app/main/ntmain.c
+++ b/src/app/main/ntmain.c
@@ -29,6 +29,8 @@
 #include "lib/evloop/compat_libevent.h"
 #include "lib/fs/winlib.h"
 #include "lib/log/win32err.h"
+#include "feature/api/tor_api.h"
+#include "feature/api/tor_api_internal.h"
 
 #include <windows.h>
 #define GENSRV_SERVICENAME  "tor"
@@ -263,7 +265,6 @@ nt_service_control(DWORD request)
 static void
 nt_service_body(int argc, char **argv)
 {
-  int r;
   (void) argc; /* unused */
   (void) argv; /* unused */
   nt_service_loadlibrary();
@@ -283,24 +284,20 @@ nt_service_body(int argc, char **argv)
     return;
   }
 
-  r = tor_init(backup_argc, backup_argv);
-  if (r) {
-    /* Failed to start the Tor service */
-    r = NT_SERVICE_ERROR_TORINIT_FAILED;
-    service_status.dwCurrentState = SERVICE_STOPPED;
-    service_status.dwWin32ExitCode = r;
-    service_status.dwServiceSpecificExitCode = r;
-    service_fns.SetServiceStatus_fn(hStatus, &service_status);
+  tor_main_configuration_t *cfg = tor_main_configuration_new();
+  cfg->run_tor_only = 1;
+  if (tor_main_configuration_set_command_line(cfg, backup_argc,
+                                              backup_argv) < 0)
     return;
-  }
 
   /* Set the service's status to SERVICE_RUNNING and start the main
    * event loop */
   service_status.dwCurrentState = SERVICE_RUNNING;
   service_fns.SetServiceStatus_fn(hStatus, &service_status);
-  set_main_thread();
-  run_tor_main_loop();
-  tor_cleanup();
+
+  tor_run_main(cfg);
+
+  tor_main_configuration_free(cfg);
 }
 
 /** Main service entry point. Starts the service control dispatcher and waits
@@ -323,29 +320,14 @@ nt_service_main(void)
     printf("Service error %d : %s\n", (int) result, errmsg);
     tor_free(errmsg);
     if (result == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
-      if (tor_init(backup_argc, backup_argv))
+      tor_main_configuration_t *cfg = tor_main_configuration_new();
+      cfg->run_tor_only = 1;
+      if (tor_main_configuration_set_command_line(cfg, backup_argc,
+                                                  backup_argv) < 0)
         return;
-      switch (get_options()->command) {
-      case CMD_RUN_TOR:
-        run_tor_main_loop();
-        break;
-      case CMD_LIST_FINGERPRINT:
-      case CMD_HASH_PASSWORD:
-      case CMD_VERIFY_CONFIG:
-      case CMD_DUMP_CONFIG:
-      case CMD_KEYGEN:
-      case CMD_KEY_EXPIRATION:
-        log_err(LD_CONFIG, "Unsupported command (--list-fingerprint, "
-               "--hash-password, --keygen, --dump-config, --verify-config, "
-               "or --key-expiration) in NT service.");
-        break;
-      case CMD_RUN_UNITTESTS:
-      case CMD_IMMEDIATE:
-      default:
-        log_err(LD_CONFIG, "Illegal command number %d: internal error.",
-                get_options()->command);
-      }
-      tor_cleanup();
+
+      tor_run_main(cfg);
+      tor_main_configuration_free(cfg);
     }
   }
 }
diff --git a/src/feature/api/tor_api_internal.h b/src/feature/api/tor_api_internal.h
index 115d33d58e..40c64e1ab8 100644
--- a/src/feature/api/tor_api_internal.h
+++ b/src/feature/api/tor_api_internal.h
@@ -29,6 +29,11 @@ struct tor_main_configuration_t {
 
   /** Socket that Tor will use as an owning control socket. Owned. */
   tor_socket_t owning_controller_socket;
+
+  /** Disable commands other than "run tor". Not for use from outside Tor
+   * itself; if you need to use this for embedding, please contact the tor
+   * developers.  */
+  int run_tor_only;
 };
 
 #endif /* !defined(TOR_API_INTERNAL_H) */