### Method

# Gio DBusConnection call_sync

since: 2.26

#### Declaration

    GVariant*
    g_dbus_connection_call_sync (
      GDBusConnection* connection,
      const gchar* bus_name,
      const gchar* object_path,
      const gchar* interface_name,
      const gchar* method_name,
      GVariant* parameters,
      const GVariantType* reply_type,
      GDBusCallFlags flags,
      gint timeout_msec,
      GCancellable* cancellable,
      GError** error
    )

#### Description

Synchronously invokes the `method_name` method on the `interface_name` D-Bus interface on the remote object at `object_path` owned by `bus_name`.

If `connection` is closed then the operation will fail with `G_IO_ERROR_CLOSED`. If `cancellable` is canceled, the operation will fail with `G_IO_ERROR_CANCELLED`. If `parameters` contains a value not compatible with the D-Bus protocol, the operation fails with `G_IO_ERROR_INVALID_ARGUMENT`.

If `reply_type` is non-`NULL` then the reply will be checked for having this type and an error will be raised if it does not match. Said another way, if you give a `reply_type` then any non-`NULL` return value will be of this type.

If the `parameters` `GVariant` is floating, it is consumed. This allows convenient ‘inline’ use of g_variant_new(), e.g.:

     g_dbus_connection_call_sync (connection,
                                  "org.freedesktop.StringThings",
                                  "/org/freedesktop/StringThings",
                                  "org.freedesktop.StringThings",
                                  "TwoStrings",
                                  g_variant_new ("(ss)",
                                                 "Thing One",
                                                 "Thing Two"),
                                  NULL,
                                  G_DBUS_CALL_FLAGS_NONE,
                                  -1,
                                  NULL,
                                  &error);

The calling thread is blocked until a reply is received. See `g_dbus_connection_call()` for the asynchronous version of this method.

Available since: 2.26

#### Parameters

`bus_name`

  Type: `const gchar*`

  A unique or well-known bus name or `NULL` if `connection` is not a message bus connection.

  The argument can be `NULL`.
  The data is owned by the caller of the method.
  The value is a NUL terminated UTF-8 string.

`object_path`

  Type: `const gchar*`

  Path of remote object.

  The data is owned by the caller of the method.
  The value is a NUL terminated UTF-8 string.

`interface_name`

  Type: `const gchar*`

  D-Bus interface to invoke method on.

  The data is owned by the caller of the method.
  The value is a NUL terminated UTF-8 string.

`method_name`

  Type: `const gchar*`

  The name of the method to invoke.

  The data is owned by the caller of the method.
  The value is a NUL terminated UTF-8 string.

`parameters`

  Type: `GVariant`

  A `GVariant` tuple with parameters for the method or `NULL` if not passing parameters.

  The argument can be `NULL`.
  The data is owned by the caller of the method.

`reply_type`

  Type: `GVariantType`

  The expected type of the reply, or `NULL`.

  The argument can be `NULL`.
  The data is owned by the caller of the method.

`flags`

  Type: `GDBusCallFlags`

  Flags from the `GDBusCallFlags` enumeration.

`timeout_msec`

  Type: `gint`

  The timeout in milliseconds, -1 to use the default timeout or `G_MAXINT` for no timeout.

`cancellable`

  Type: `GCancellable`

  A `GCancellable` or `NULL`.

  The argument can be `NULL`.
  The data is owned by the caller of the method.

`error`

  Type: `GError **`

  The return location for a recoverable error.

  The argument can be `NULL`.
  If the return location is not `NULL`, then you must initialize it to a `NULL` `GError*`.
  The argument will be left initialized to `NULL` by the method if there are no errors.
  In case of error, the argument will be set to a newly allocated `GError`; the caller will take ownership of the data, and be responsible for freeing it.

#### Return value

Type: `GVariant`

`NULL` if `error` is set. Otherwise a non-floating `GVariant` tuple with return values. Free with g_variant_unref().

The caller of the method takes ownership of the data, and is responsible for freeing it.