Here is a brief guide on how to build the SRI LM tools and associated
libraries.

1 - Unpack.  This should give a top-level directory with the subdirectories
    listed in README, as well as a few documentation files and a Makefile.
    For an overview of SRILM, see the paper in doc/paper.ps .
    For reference information, look in man/html .

2 - Set the SRILM variable in the top-level Makefile to point to this
    top-level directory (an absolute path).

3 - You need a SunOS (Sparc or i386), IRIX 5.x, Alpha OSF, Linux i686, Mac OSX,
    or CYGWIN platform to compile out of the box.  For other OS/cpu combinations
    you will have to modify the sbin/machine-type script to detect (and name)
    the platform type, and create a file common/Makefile.machine.<platform>
    that defines platform-dependent makefile variables.
    As a workaround, the MACHINE_TYPE variable can also be set on the make
    comand line
			make MACHINE_TYPE=foo ...

    in which case no changes to sbin/machine-type are needed.

    Some platform-specific notes may be found in doc/README.<platform>.

    Even on the known platforms you might have to edit
    common/Makefile.machine.<platform> .  Candidates for changes are

    CC, CXX: 	choose compiler or compiler version.  For example, you will
		probably have to change the path to the compiler driver.
    DEMANGLE_FILTER:  If the "c++filt" program is not installed on your system
		set this variable to empty.
    TCL_INCLUDE, TCL_LIBRARY:  to whatever is needed to find the Tcl header
		files and library.

    If Tcl is not available, set NO_TCL=X and leave the above variables empty.

4 - You need the following free third-party software to build SRILM:

	- gcc version 3.4.3 or higher
	  (older versions might work as well, but are no longer supported).
	  SRILM is occasionally tested with other compilers, see the 
	  portability notes in the CHANGES file.
	- GNU make 
	- John Ousterhout's Tcl toolkit, version 7.3 or higher
	  (this is currently used only for some test programs, but is needed
	  for the build to go through without manual intervention).
	- Additional platform-dependent prerequisites are mentioned in
	  doc/README.<os>-<machinetype>, e.g., doc/README.windows-cygwin.

    The following tools are needed at runtime only:

	- GNU awk (gawk), to interpret many of the utility scripts
	- gzip, to read/write compressed files
	- bzip2, to read/write .bz2 compressed files (optional)
	- p7zip, to read/write .7z compressed files (optional)

    For Windows 9x or NT, you will need the CYGWIN UNIX compatibility 
    environment, which includes all of the above.  The MinGW and
    Visual C platforms will also work, but with some loss of functionality.
    See doc/README.windows-* for more information.

    Links to these packages can be found on the SRILM download page
    (http://www.speech.sri.com/projects/srilm/download.html).

5 - In the top-level directory, run

	gnumake World		or 
	make World		(if the GNU version is the system default)

    This will create the directories

	bin/
	lib/
	include/

    build everything and install public commands, libraries and headers in
    these directories.  Binaries are actually installed in subdirectories
    indicating the platform type.

    To create binaries for a platform that is not the default on your system,
    use make MACHINE_TYPE=xxx, e.g.

 	make MACHINE_TYPE=i686-m64 World	# 64-bit binaries for Linux
 	make MACHINE_TYPE=msvc World		# MS Visual C++ on Windows 

6 - The result of the above should be a fair number of .h and .cc files in
    include/, libraries in lib/$MACHINE_TYPE, and programs in 
    bin/$MACHINE_TYPE.  In your shell, set the following environment
    variables:

	PATH		add $SRILM/bin/$MACHINE_TYPE and $SRILM/bin
	MANPATH		add $SRILM/man

7 - To test the compiled tools, change into the $SRILM/test directory and run

	gnumake all

    This exercises the most important (though not all) functionality in
    SRILM and compares the results to reference outputs.  If discrepancies are 
    reported, examine the output files in $SRILM/test/output and compare them
    to the corresponding files in $SRILM/test/reference.

8 - After a successful build, clean up the source directories of object and 
    binary files that are no longer needed:

	gnumake cleanest

9 - (Optional) To build versions of the libraries and executables that are 
    optimized for space rather than speed, run

	gnumake World OPTION=_c
	gnumake cleanest OPTION=_c

    The libraries will appear in ${SRILM}/lib/${MACHINE_TYPE}_c, with 
    executables in ${SRILM}/bin/${MACHINE_TYPE}_c .  The data structures
    used in these versions use sorted arrays rather than hash tables, which
    wastes less memory, but is also somewhat slower. The directory suffix "_c"
    stands for "compact".

    Other versions of the binaries can be built in a similar manner.
    The compile options currently supported are 

	OPTION=_c	"compact" data structures
	OPTION=_s	"short" count representation
	OPTION=_l	"long long" count representation
	OPTION=_g	debuggable, non-optimized code
	OPTION=_p	profiling executables

10 - Recent versions of gawk may not perform correct floating-point arithmetic
     unless either

		LC_NUMERIC=C	or
		LC_ALL=C

     is set in the environment.  This affects many of the scripts in utils/.

11 - Be sure to let me know if I left something out.

Andreas Stolcke
stolcke@speech.sri.com
$Date: 2007/11/11 16:47:05 $