Notes on using IT++ on Athena by alexp (Alex Prengel) 
                                                                  2/26/08

The IT++ libraries (along with multiple helper libraries) have been installed 
on Athena for Sun and Linux. All libraries and binaries were built from 
source; the compilers used (and hence recommended compiler) are:

Sun: gcc/g++/g77 in gcc-3.4 locker:

gcc version 3.4.4

Linux: default  gcc/g++/g77 in Athena 9.4 release:

gcc version 3.4.6 20060404 (Red Hat 3.4.6-9)

Both static and dynamic libraries have been built; however fully
static binaries are generally not possible as libc and libX11, needed
by most applications, are not available in static form on all platforms.

You will need to add the itpp locker. Sourcing the file
/mit/itpp/cshrc after this will set proper paths and environment 
variables for building your applications.

The itpp-config utility, located in the  itpp_v4.0.2 locker (and accessible
from the itpp locker) can be used to determine compiler and linker flags
suitable for building your applications- typing " itpp-config --help" gives
usage information.

You will need to use include files in /mit/itpp_v4.0.2/include in your
applications, i.e. like:

#include <itpp/itbase.h>

(or whatever other includes your application requires) and link
against libraries in /mit/itpp_v4.0.2/lib; generally you will need to
use multiple libraries in this directory, and various other system 
libraries.

You should use itpp-config output to generate the command-line, i.e.

g++ -O2 `itpp-config --cflags` -o myfile myfile.cpp `itpp-config --libs`

NOTE: `itpp-config --libs` may not always supply the full needed library list,
and you may get "undefined symbol" errors in some cases. Linking against
additional libraries in /mit/itpp_v4.0.2/lib will usually fix this.

See comments in file example.cpp in the same directory as this file for a
specific example.

When you run dynamically linked binaries you build with IT++ later, you
will need to point the runtime system to the dynamic libraries through
the LD_LIBRARY_PATH environment variable. This is done automatically
if you add the itpp locker and source /mit/itpp/cshrc (setting
ITPP_VERSION if you are not using the default version), but you
probably won't want to do this every time you run something. A fairly
simple way around this is to rename your binary and use a small
"wrapper" script. If your binary is "foo", rename it to "foo.real",
and write a shell script called "foo" as follows:

#!/bin/csh -f
set HERE=`dirname $0`
if (-e /etc/athena/reactivate) then
set isathena=1
attach -q itpp
else
set isathena=0
setenv ATHENA_SYS `fs sysname | awk '{ print substr($4,2,length($4)-2)}'`
afslocker itpp >/dev/null
endif
if ( ! $?ITPP_VERSION) then
setenv ITPP_LOCKER itpp-default
else
setenv ITPP_LOCKER ITPP_v${ITPP_VERSION}
endif
setenv MACHINE `machtype`
if ($MACHINE == sun4) then
  set addpath=/mit/itpp/${ITPP_LOCKER}/lib:/usr/sfw/lib/sparcv9
else
  set addpath=/mit/itpp/${ITPP_LOCKER}/lib
endif
if ( $?LD_LIBRARY_PATH ) then
setenv LD_LIBRARY_PATH ${addpath}:$LD_LIBRARY_PATH
else
setenv LD_LIBRARY_PATH ${addpath}
endif
exec ${HERE}/foo.real $*

or the equivalent with the Bourne shell. PLEASE NOTE THAT WE CAN'T
GUARANTEE THAT DYNAMIC LIBRARIES WILL STAY AROUND INDEFINITELY IN THE
SAME LOCATIONS THEY ARE IN NOW! THIS MAY BREAK DYNAMICALLY LINKED
BINARIES!  You may want to copy the relevant dynamic libraries to a
location of your choosing, or use static linking instead.

Note that the current default version of the library will be used, but this
may be overridden by setting the ITPP_VERSION environment variable at run time.

Online documentation is at http://itpp.sourceforge.net/current/