1. Cornell Theory Center Aug 23 2000 Porting CCTK to NT at the Cornell Velocity NT Cluster Werner Benger Max-PIanck-Institut für Gravitationsphysik (Albert-Einstein-Institute at Golm/Potsdam – AEI) and Konrad-Zuse-Center for Information Technology Berlin (ZIB) Werner.Benger@aei-potsdam.mpg.de

2. = CYGWIN – Unix GNU Make " CCTK makefiles using lots of gmake special functions = Bash " more powerfull than command.com " Required for `autoconf' configure script " Some shell-commands used in makefiles = Sed " Command line argument conversions when gmake functionality or shell commands are not sufficient = Perl " CCTK Flesh-Thorn interfaces consists of code generated by perl scripts from description files in `Cactus Configuration Language' -.ccl files " Preprocessing of F77,F90,C,C++ = Compilers: C, (C++,) [F77, F90] Porting Cactus to NT – Requirements

3. Early Difficulties = PERL! " Required at the very earliest step, directly invoked from makefile = ActiveState Perl is installed on the NT Cluster " Incompatible to cygwin perl " Cygwin uses unix-like path names: – /cygdrive/c/temp/Werner/Cactus – //c/temp/Werner/Cactus " ActiveState Perl uses DOS/Windows like path names: – c:\temp\Werner\Cactus c:\temp\Werner\Cactus = Cygwin perl needed to be installed on local workstation, no installation on NT Cluster " Compilation only possible locally = Installation of cygwin perl on NT cluster in local homedir works, but need to specify perl include path on each invokation... = Compilation on NT Cluster very slow anyway...

4. Cygwin = Cygwin 5.0 installed " Not yet supported by CCTK " Introduces the /cygdrive/ prefix – /cygdrive/c/ for //c in earlier version or c:\ in DOS/Windowsc:\ " Had to adjust makefile includes in a couple of places – $(subst /cygdrive/,//, ) backward compatibility to cygwin 4.0 " external/IEEEIO library explicitely looking for CYGWIN_NT-4.0 – Added support for CYGWIN_NT-5.0 = Environment now set up for use of gcc cygwin compiler – but we want Visual C++!

5. Cygwin and MS Visual C++ = Unix compiler vs. MS compiler " Path names: c:\temp\Werner\Cactus vs. //c/temp/Werner/Cactusc:\temp\Werner\Cactus " Command line switches: /Ic:\library\include -I/include " Extensions: – Object files:.o vs..obj works, as MSC treats unkown extensions as object files – Libraries: lib.a vs. xxx.lib lib/make/make.thornlib to be modified to transform unix libname into MSC libname – Executable:.exe Ok, already handled " Still want to use cygwin gcc to create dependency information for makefiles – In some parts cygwin pathnames and parameters – Other parts MSC pathnames and parameters – Pathname conversion routines required – #define's and #include paths from MSC need to be set for gcc, too!

6. Pathname Conversion = Task: Convert /cygdrive/c/temp/Werner/ to c:\temp\Wernerc:\temp\Werner " Using sed is powerful, but requires external tool and is slow " GNU make functions are fast, but limited " Well, can still be done: LETTERS= a b c d e f g h i j k l m n o p q r s t u v w x y z \ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z INCLUDE_PARAMETERS=$(subst -I,/I,$(subst /,\\, $(foreach DRIVE, $(LETTERS), $(filter - I$(DRIVE):%,$(subst //$(DRIVE),$(DRIVE):,$(subst /cygdrive/,//,$(INC_DIRS:%=-I%))))))) INC_DIRS=/cygdrive/h/PROGRA~1/MPIPRO //c/PROGRA~1/MICROS~2/VC98/INCLUDE show: @echo INC_DIRS=$(INC_DIRS) @echo INCLUDE_PARAMETERS=$(INCLUDE_PARAMETERS) WEYL://c/temp/werner $ make show INC_DIRS=/cygdrive/h/PROGRA~1/MPIPRO //c/PROGRA~1/MICROS~2/VC98/INCLUDE INCLUDE_PARAMETERS= /Ic:\PROGRA~1\MICROS~2\VC98\INCLUDE /Ih:\PROGRA~1\MPIPRO WEYL://c/temp/werner $

7. Properties of Pathname conversion = - Pathnames must not contain spaces " Uses windows shortcut names instead of long names – //c/PROGRA~1/MICROS~2/VC98/INCLUDE – //c/Program Files/Microsoft Visual Studio/VC98/INCLUDE " Find out by starting `command.com' from bash = + Late evalutation in make " May define make expression first " May set of variable to expanded later " Make function is evaluated not before it is actually used = + Much faster than calling sed scripts = + Doesn't require external tool (directly portable) = - Need to copy the expression for each make variable to be used = - Hardly readable... so better don't touch and avoid using too often

8. Minor changes = Support for MPIPro  Added shell script: lib/make/extras/MPI/MPIPro  Some fixes in the lib/make/know-architectures/cygwin default variables " CC=cl " CXX="$CC /TP" " AR=lib " Etc. = Editing Thornlist: " `preferred editor' is `notepad' under Windows " Changed lib/make/make.configuration " But this might be a matter of taste, other people might still prefer `vi'... " Can't run notepad from telnet session...

9. Networking = TCP calls (mostly already done for SC99 NCSA NT Cluster) " Similar, but still minor differences between Unix and Windows – read(),write() vs. recv(), send() – close() vs. Closesocket() – etc. " Conversion of socket descriptor to file descriptor not possible (?) " Cannot use C++ Standard Stream library for sockets!? – No ofstream(int fd) constructor... – Had to provide a `stream emulator class' under windows = TCP Initialization " Windows Socket Layer must be initialized before any TCP networking works!!  WSAStartup() " C++ Constructor Call or CCTK Startup Routine = HTTP Support for MSIE " Requires explicit HTTP header where netscape doesn't " `Movie Thorn': multipart encoding of streamed jpeg images works with Netscape, but not yet with MSIE... (?)

10. At last: it worked.