execute_process: Document {OUTPUT,ERROR}_STRIP_TRAILING_WHITESPACE
diff --git a/Help/command/execute_process.rst b/Help/command/execute_process.rst
index c2c7fe3..a2f9036 100644
--- a/Help/command/execute_process.rst
+++ b/Help/command/execute_process.rst
@@ -121,6 +121,10 @@
and standard error pipes, respectively. If the same variable is named
for both pipes their output will be merged in the order produced.
+``OUTPUT_STRIP_TRAILING_WHITESPACE``, ``ERROR_STRIP_TRAILING_WHITESPACE``
+ Removes whitespace characters from the end of the values stored in the
+ corresponding ``OUTPUT_VARIABLE`` and ``ERROR_VARIABLE`` variables.
+
``ECHO_OUTPUT_VARIABLE``, ``ECHO_ERROR_VARIABLE``
.. versionadded:: 3.18
