Try to avoid dupliate build

Author: hosiet

CMakeLists.txt

@@ -35,7 +35,6 @@ endif ()
 set(builtstamp "${CMAKE_BINARY_DIR}/.builtstamp")
 add_custom_target(man ALL DEPENDS ${builtstamp})
 
-
 set(MANDIR_LIST "man1" "man2" "man3" "man4" "man5" "man6" "man7" "man8" "mann")
 
 foreach (MANDIR ${MANDIR_LIST})
@@ -76,19 +75,27 @@ foreach (MANDIR ${MANDIR_LIST})
         if (ENABLE_ZHCN)
             add_custom_target(man_zhcn_${MAN_PAGE_NAME}_dir
                 COMMAND ${CMAKE_COMMAND} -E make_directory
-                ${MAN_PAGE_PREPAREDIR_ZHCN})
+                ${MAN_PAGE_PREPAREDIR_ZHCN}
+                OUTPUT ${MAN_PAGE_PREPAREDIR_ZHCN}
+            )
             add_custom_target(man_zhcn_${MAN_PAGE_NAME}_build
-                COMMAND ${PROCESS_COMMAND_ZHCN})
+                COMMAND ${PROCESS_COMMAND_ZHCN}
+                OUTPUT ${PROCESS_OUTPUT_ZHCN}
+            )
             add_dependencies(man man_zhcn_${MAN_PAGE_NAME}_build)
             add_dependencies(man_zhcn_${MAN_PAGE_NAME}_build man_zhcn_${MAN_PAGE_NAME}_dir)
             cmake_print_variables(PROCESS_COMMAND_ZHCN)
         endif (ENABLE_ZHCN)
         if (ENABLE_ZHTW)
             add_custom_target(man_zhtw_${MAN_PAGE_NAME}_dir
                 COMMAND ${CMAKE_COMMAND} -E make_directory
-                ${MAN_PAGE_PREPAREDIR_ZHTW})
+                ${MAN_PAGE_PREPAREDIR_ZHTW}
+                OUTPUT ${MAN_PAGE_PREPAREDIR_ZHTW}
+            )
             add_custom_target(man_zhtw_${MAN_PAGE_NAME}_build
-                COMMAND ${PROCESS_COMMAND_ZHTW})
+                COMMAND ${PROCESS_COMMAND_ZHTW}
+                OUTPUT ${PROCESS_OUTPUT_ZHTW}
+            )
             add_dependencies(man man_zhtw_${MAN_PAGE_NAME}_build)
             add_dependencies(man_zhtw_${MAN_PAGE_NAME}_build man_zhtw_${MAN_PAGE_NAME}_dir)
         endif (ENABLE_ZHTW)