ctest_update
------------

Perform the :ref:`CTest Update Step` as a :ref:`Dashboard Client`.

::

  ctest_update([SOURCE <source-dir>] [RETURN_VALUE <result-var>] [QUIET])

Update the source tree from version control and record results in
``Update.xml`` for submission with the :command:`ctest_submit` command.

The options are:

``SOURCE <source-dir>``
  Specify the source directory.  If not given, the
  :variable:`CTEST_SOURCE_DIRECTORY` variable is used.

``RETURN_VALUE <result-var>``
  Store in the ``<result-var>`` variable the number of files
  updated or ``-1`` on error.

``QUIET``
  Tell CTest to suppress most non-error messages that it would
  have otherwise printed to the console.  CTest will still report
  the new revision of the repository and any conflicting files
  that were found.