manpagez: man pages & more
man mpijavac(1)
Home | html | info | man
mpijava(1)                         Open MPI                         mpijava(1)


       mpijava -- Open MPI Java wrapper compiler


       mpijava [-showme|-showme:compile|-showme:link] ...


              This  option  comes  in  several different variants (see below).
              None of the variants invokes the underlying compiler;  they  all
              provide  information  on  how the underlying compiler would have
              been invoked had --showme not been  used.   The  basic  --showme
              option  outputs  the command line that would be executed to com-
              pile the program.  NOTE: If a non-filename argument is passed on
              the  command line, the -showme option will not display any addi-
              tional flags.  For example, both "mpijava --showme" and "mpijava
              --showme"  will  show  all  the wrapper-supplied
              flags.  But "mpijava --showme -v" will only show the  underlying
              compiler name and "-v".

              Output  the  compiler flags that would have been supplied to the
              java compiler.

              Output the linker flags that would have  been  supplied  to  the
              java compiler.

              Outputs  the  underlying java compiler command (which may be one
              or more tokens).

              Outputs a space-delimited (but otherwise  undecorated)  list  of
              directories that the wrapper compiler would have provided to the
              underlying java compiler to indicate where relevant header files
              are located.

              Outputs  a  space-delimited  (but otherwise undecorated) list of
              directories that the wrapper compiler would have provided to the
              underlying  linker  to  indicate  where  relevant  libraries are

              Outputs a space-delimited (but otherwise  undecorated)  list  of
              library  names that the wrapper compiler would have used to link
              an application.  For example: "mpi open-rte open-pal util".

              Outputs the version number of Open MPI.

       See the man page for your underlying java compiler  for  other  options
       that can be passed through mpijava.


       Conceptually, the role of these commands is quite simple: transparently
       add relevant compiler and linker flags to the user's command line  that
       are  necessary to compile / link Open MPI programs, and then invoke the
       underlying compiler to actually perform the command.

       As such, these commands are frequently referred to as "wrapper" compil-
       ers  because  they  do  not actually compile or link applications them-
       selves; they only add in command line flags  and  invoke  the  back-end

       mpijava  is  a  convenience  wrapper  for the underlying java compiler.
       Translation of an Open MPI program requires the  linkage  of  the  Open
       MPI-specific  libraries  which  may  not  reside in one of the standard
       search directories of ld(1).  It also often requires the  inclusion  of
       header files what may also not be found in a standard location.

       mpijava passes its arguments to the underlying java compiler along with
       the -I, -L and -l options required by Open MPI programs.

       The Open MPI Team  strongly  encourages  using  the  wrapper  compilers
       instead of attempting to link to the Open MPI libraries manually.  This
       allows the specific implementation of Open MPI to change without  forc-
       ing changes to linker directives in users' Makefiles.  Indeed, the spe-
       cific set of flags and libraries used by the wrapper compilers  depends
       on how Open MPI was configured and built; the values can change between
       different installations of the same version of Open MPI.

       Indeed, since the wrappers are simply thin shells on top of an underly-
       ing  compiler,  there  are very, very few compelling reasons not to use
       mpijava.  When it is not possible to use  the  wrappers  directly,  the
       -showme:compile  and  -showme:link  options should be used to determine
       what flags the wrappers would have used.


       It is possible to make the wrapper compilers multi-lib aware.  That is,
       the  libraries  and includes specified may differ based on the compiler
       flags specified (for example, with the GNU compilers on Linux,  a  dif-
       ferent  library  path  may  be  used  if -m32 is seen versus -m64 being
       seen).  This is not the default behavior in a standard build,  but  can
       be activated (for example, in a binary package providing both 32 and 64
       bit support).  More information can be found at:


       The string that the wrapper compilers  insert  into  the  command  line
       before  invoking the underlying compiler are stored in a text file cre-
       ated by Open MPI and  installed  to  $pkgdata/mpijava-wrapper-data.txt,
       where  $pkgdata  is typically $prefix/share/openmpi, and $prefix is the
       top installation directory of Open MPI.

       It is rarely necessary to edit this file, but it  can  be  examined  to
       gain  insight  into  what flags the wrappers are placing on the command


       By default, the wrappers use the compilers that were selected when Open
       MPI was configured.  These compilers were either found automatically by
       Open MPI's "configure" script, or were selected by the user in the  CC,
       CXX, F77, JAVAC, and/or FC environment variables before "configure" was
       invoked.  Additionally, other arguments specific to  the  compiler  may
       have been selected by configure.

1.7a1r25839M               Unreleased developer copy                mpijava(1)

openmpi 1.8 - Generated Fri May 9 15:13:55 CDT 2014
© 2000-2021
Individual documents may contain additional copyright information.