Index: /trunk/FACT++/CMakeLists.txt
===================================================================
--- /trunk/FACT++/CMakeLists.txt	(revision 19277)
+++ /trunk/FACT++/CMakeLists.txt	(revision 19278)
@@ -78,13 +78,17 @@
 
 # ========== executables ==========
-FIND_PROGRAM(HELP2MAN_EXECUTABLE help2man)
-FIND_PROGRAM(ROFFHTML_EXECUTABLE roff2html)
-FIND_PROGRAM(ROFFPDF_EXECUTABLE  roff2pdf)
-FIND_PROGRAM(GROFF_EXECUTABLE    groff)
+FIND_PROGRAM(HELP2MAN_EXECUTABLE  help2man)
+FIND_PROGRAM(ROFF2HTML_EXECUTABLE roff2html)
+FIND_PROGRAM(ROFF2PDF_EXECUTABLE  roff2pdf)
+FIND_PROGRAM(GROFF_EXECUTABLE     groff)
 
 FIND_PACKAGE_HANDLE_STANDARD_ARGS(help2man  DEFAULT_MSG HELP2MAN_EXECUTABLE)
-FIND_PACKAGE_HANDLE_STANDARD_ARGS(roff2html DEFAULT_MSG ROFFHTML_EXECUTABLE)
-FIND_PACKAGE_HANDLE_STANDARD_ARGS(roff2pdf  DEFAULT_MSG ROFFPDF_EXECUTABLE)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(roff2html DEFAULT_MSG ROFF2HTML_EXECUTABLE)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(roff2pdf  DEFAULT_MSG ROFF2PDF_EXECUTABLE)
 FIND_PACKAGE_HANDLE_STANDARD_ARGS(groff     DEFAULT_MSG GROFF_EXECUTABLE)
+
+IF (NOT HELP2MAN_EXECUTABLE OR NOT ROFF2HTML_EXECUTABLE OR NOT ROFF2PDF_EXECUTABLE OR NOT GROFF_EXECUTABLE)
+MESSAGE(STATUS "Documentation turned off (some executables missing).")
+ENDIF()
 
 IF (NOT TOOLS_ONLY)
@@ -432,5 +436,5 @@
 MACRO(MANPAGE program description)
 # https://samthursfield.wordpress.com/2015/11/21/cmake-dependencies-between-targets-and-files-and-custom-commands/
-IF (HELP2MAN_EXECUTABLE AND ROFFHTML_EXECUTABLE AND ROFFPDF_EXECUTABLE AND GROFF_EXECUTABLE)
+IF (HELP2MAN_EXECUTABLE AND ROFF2HTML_EXECUTABLE AND ROFF2PDF_EXECUTABLE AND GROFF_EXECUTABLE)
         ADD_CUSTOM_COMMAND(
         	OUTPUT