cw: don't shadow pure pre-processing
cw(1onbld): --shadow not --secondary

@@ -15,15 +15,15 @@
      so that warnings and errors may be obtained from both.  See SHADOW
      COMPILATION for details.  This version of cw supports compilers with both
      Sun Studio 12 and GCC-style command lines.
 
 ARGUMENTS
-     Both the --primary and --secondary parameters take a compiler
-     specification.  This is a comma-separated list of the form
-     name,executable,style Where name is a name for the compiler, executable
-     is the full path to the compiler executable, and style is the style of
-     command-line options the compiler expects, either sun or gnu.
+     Both the --primary and --shadow parameters take a compiler specification.
+     This is a comma-separated list of the form name,executable,style Where
+     name is a name for the compiler, executable is the full path to the
+     compiler executable, and style is the style of command-line options the
+     compiler expects, either sun or gnu.
 
      --primary compiler
              Specify the compiler to be used primarily (that which is used for
              link-editing and pre-processing, and whos objects we deliver).
 

@@ -62,26 +62,24 @@
 SHADOW COMPILATION
      If --shadow compilers are specified cw will invoke shadow compiler, with
      the outputs modified (as well as any translation for compiler style) as
      follows:
 
-     1.   If none of -c, -E, -P, or -S appears in the argument list (that is,
-          linking is attempted), the shadow compilers will not be invoked.
-          This is because the objects built with that compiler which would be
-          linked have been previously discarded.
+     1.   If neither of -c, -S appears in the argument list (that is, linking
+          is attempted or only the pre-processor is invoked), the shadow
+          compilers will not be invoked.
 
      2.   If the -o filename option was provided, with or without a separating
           space, it will be replaced with -o tempfile
 
      3.   If the option -o was not provided, -o tempfile will be added to the
           end of the argument list used to invoke the shadow compilers.
      When shadow compilation is in effect, cw writes to standard error each
      compiler's standard error output following its argument list.  Messages
      from the compilers will not be interleaved.  If cw is used to invoke the
      preprocessor and no output location is specified, cw will write to
-     standard output the primary compiler's standard output, and the secondary
-     compiler's standard output will be discarded.
+     standard output the primary compiler's standard output.
 
      Because the Sun compilers write intermediate objects to fixed filenames
      in the current directory when instructed to compile and link multiple
      source files via a single command line, it would be unsafe to invoke more
      than one compiler in this fashion.  Therefore cw does not accept multiple