> On 2015-06-09, at 8:05 AM, David Cole <dlrd...@aol.com> wrote: > > Why not just use configure_file
because I didn’t know about it. Thanks! > to write ${metals} into the file... > configure_file only actually touches/writes-to/updates the file if the > contents are different... > > Then you can just depend on that file and you don't need a separate > timestamp file. > > > HTH, > David C. > > > On Tue, Jun 9, 2015 at 1:05 AM, Dave Yost <d...@yost.com> wrote: >> >> >> First, my cmake code does this: >> >> sets ${metals} from a cmake command-line argument >> compares the contents of ${metals} against the contents of a file to note >> whether the variable is being changed since the last run of cmake >> writes the new value to that file for next time >> call an add_timestamp_file_target function. which touches the file >> metalsTimestamp if the variable is being changed or if the file doesn’t >> exist. >> >> Then comes this: >> >> set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DMETALS=\"\\\"${metals}\\\"\"") >> add_executable (metals metals.cc) >> add_dependencies (metals metalsTimestamp) >> >> >> My add_timestamp_file_target function has to use one of >> add_custom_target >> add_custom_command >> to make metalsTimestamp visible to the add_dependencies function. >> >> Problem is, it seems that those commands have to touch the file every time >> cmake runs, but I want to touch it only when necessary. >> >> Is there a way to make this work? >> >> >> -- >> >> Powered by www.kitware.com >> >> Please keep messages on-topic and check the CMake FAQ at: >> http://www.cmake.org/Wiki/CMake_FAQ >> >> Kitware offers various services to support the CMake community. For more >> information on each offering, please visit: >> >> CMake Support: http://cmake.org/cmake/help/support.html >> CMake Consulting: http://cmake.org/cmake/help/consulting.html >> CMake Training Courses: http://cmake.org/cmake/help/training.html >> >> Visit other Kitware open-source projects at >> http://www.kitware.com/opensource/opensource.html >> >> Follow this link to subscribe/unsubscribe: >> http://public.kitware.com/mailman/listinfo/cmake -- Powered by www.kitware.com Please keep messages on-topic and check the CMake FAQ at: http://www.cmake.org/Wiki/CMake_FAQ Kitware offers various services to support the CMake community. For more information on each offering, please visit: CMake Support: http://cmake.org/cmake/help/support.html CMake Consulting: http://cmake.org/cmake/help/consulting.html CMake Training Courses: http://cmake.org/cmake/help/training.html Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Follow this link to subscribe/unsubscribe: http://public.kitware.com/mailman/listinfo/cmake