Description

   By default, child processes created by one of the exec family of
   functions inherit the default (working) directory of their parent
   process.

   The decc$set_child_default_dir function lets you set the
   default directory for a child process. After calling decc$set_
   child_default_dir, newly spawned child processes have their
   default directory set to default_dir as they begin execution.
   The default_dir argument must represent a valid directory
   specification, or results of the call are unpredictable
   (subsequent calls to the child process might fail without
   notification). Both OpenVMS and UNIX style file specifications
   are supported for this function call.

   You can reestablish the default behavior by specifying default_
   dir as NULL. Subsequently, newly created child processes will
   inherit their parent's working directory.