scm

SCM(Jan 4 2000)                                                SCM(Jan 4 2000)



NAME
       scm - a Scheme Language Interpreter

SYNOPSIS
       scm [-a kbytes ] [-muvqib] [--version] [--help]
       [[-]-no-init-file] [-p int ] [-r feature ] [-h feature ]
       [-d filename ] [-f filename ] [-l filename ]
       [-c expression ] [-e expression ] [-o dumpname ]
       [-- | - | -s] [ filename ] [ arguments ...  ]

DESCRIPTION
       Scm is a Scheme interpreter.

       Upon startup scm loads the file specified by by the environment
       variable SCM_INIT_PATH or by the parameter IMPLINIT in the makefile (or
       scmfig.h) if SCM_INIT_PATH is not defined.  The makefiles attempt to
       set IMPLINIT to "Init.scm" in the source directory.

       Unless the option -no-init-file or --no-init-file occurs in the command
       line, "Init.scm" checks to see if there is file "ScmInit.scm" in the
       path specified by the environment variable HOME (or in the current
       directory if HOME is undefined).  If it finds such a file it is loaded.

       "Init.scm" then looks for command input from one of three sources: From
       an option on the command line, from a file named on the command line,
       or from standard input.


OPTIONS
       The options are processed in the order specified on the command line.

       -akbytes
            specifies that scm should allocate an initial heapsize of kbytes.
            This option, if present, must be the first on the command line.

       -no-init-file
            Inhibits the loading of "ScmInit.scm" as described above.

       -eexpression

       -cexpression
            specifies that the scheme expression expression is to be
            evaluated.  These options are inspired by perl and sh
            respectively.  On Amiga systems the entire option and argument
            need to be enclosed in qoutes.  For instance "-e(newline)".

       -rfeature
            requires feature.  This will load a file from SLIB if that feature
            is not already supported.  If feature is 2, 3, 4, or 5 scm will
            require the features neccessary to support R2RS, R3RS, R4RS, or
            R5RS, respectively.

       -hfeature
            provides feature.

       -lfilename

       -ffilename
            loads filename.  Scm will load the first (unoptioned) file named
            on the command line if no -c, -e, -f, -l, or -s option preceeds
            it.

       -dfilename
            opens (read-only) the extended relational database filename.  If
            filename contains initialization code, it will be run when the
            database is opened.

       -odumpname
            saves the current SCM session as the executable program dumpname.
            This option works only in SCM builds supporting dump.

            If options appear on the command line after -o dumpname, then the
            saved session will continue with processing those options when it
            is invoked.  Otherwise the (new) command line is processed as
            usual when the saved image is invoked.

       -plevel
            sets the prolixity (verboseness) to level.  This is the same as
            the scm command (verobse level ).

       -v   (verbose mode) specifies that scm will print prompts, evaluation
            times, notice of loading files, and garbage collection statistics.
            This is the same as -p3.

       -q   (quiet mode) specifies that scm will print no extra information.
            This is the same as -p0.

       -m   specifies that subsequent loads, evaluations, and user
            interactions will be with R4RS macro capability.  To use a
            specific R4RS macro implementation from SLIB (instead of SLIB's
            default) put -r macropackage before -m on the command line.

       -u   specifies that subsequent loads, evaluations, and user
            interactions will be without R4RS macro capability.  R4RS macro
            capability can be restored by a subsequent -m on the command line
            or from Scheme code.

       -i   specifies that scm should run interactively.  That means that scm
            will not terminate until the (quit) or (exit) command is given,
            even if there are errors.  It also sets the prolixity level to 2
            if it is less than 2.  This will print prompts, evaluation times,
            and notice of loading files.  The prolixity level can be set by
            subsequent options.  If scm is started from a tty, it will assume
            that it should be interactive unless given a subsequent -b option.

       -b   specifies that scm should run non-interactively.  That means that
            scm will terminate after processing the command line or if there
            are errors.

       -s   specifies, by analogy with sh, that further options are to be
            treated as program aguments.

       -    -- specifies that there are no more options on the command line.

ENVIRONMENT VARIABLES
       SCM_INIT_PATH
            is the pathname where scm will look for its initialization code.
            The default is the file "Init.scm" in the source directory.

       SCHEME_LIBRARY_PATH
            is the SLIB Scheme library directory.

       HOME is the directory where "Init.scm" will look for the user
            initialization file "ScmInit.scm".

SCHEME VARIABLES
       *argv*
            contains the list of arguments to the program.  *argv* can change
            during argument processing.  This list is suitable for use as an
            argument to SLIB getopt.

       *R4RS-macro*
            controls whether loading and interaction support R4RS macros.
            Define this in "ScmInit.scm" or files specified on the command
            line.  This can be overridden by subsequent -m and -u options.

       *interactive*
            controls interactivity as explained for the -i and -b options.
            Define this in "ScmInit.scm" or files specified on the command
            line.  This can be overridden by subsequent -i and -b options.

EXAMPLES
       % scm foo.scm arg1 arg2 arg3
            Load and execute the contents of foo.scm.  Parameters arg1 arg2
            and arg3 are stored in the global list *argv*.

       % scm -f foo.scm arg1 arg2 arg3
            The same.

       % scm -s foo.scm arg1 arg2
            Set *argv* to ("foo.scm" "arg1" "arg2") and enter interactive
            session.

       % scm -e '(display (list-ref *argv* *optind*))' bar
            Print ``bar''

       % scm -rpretty-print -r format -i
            Load pretty-print and format and enter interactive mode.

       % scm -r5
            Load dynamic-wind, values, and R4RS macros and enter interactive
            (with macros) mode.

       % scm -r5 -r4
            Like above but rev4-optional-procedures are also loaded.

FEATURES
       Runs under Amiga, Atari-ST, MacOS, MS-DOS, OS/2, NOS/VE, Unicos, VMS,
       Unix and similar systems.  Support for ASCII and EBCDIC character sets.

       Conforms to Revised^5 Report on the Algorithmic Language Scheme and the
       IEEE P1178 specification.

       Support for SICP, R2RS, R3RS, and R4RS scheme code.

       Many Common Lisp functions: logand, logor, logxor, lognot, ash,
       logcount, integer-length, bit-extract, defmacro, macroexpand,
       macroexpand1, gentemp, defvar, force-output, software-type, get-
       decoded-time, get-internal-run-time, get-internal-real-time, delete-
       file, rename-file, copy-tree, acons, and eval.

       Char-code-limit, most-positive-fixnum, most-negative-fixnum, and
       internal-time-units-per-second constants.  *Features* and *load-
       pathname* variables.

       Arrays and bit-vectors.  String ports and software emulation ports.
       I/O extensions providing most of ANSI C and POSIX.1 facilities.

       User definable responses to interrupts and errors, Process-
       syncronization primitives, String regular expression matching, and the
       CURSES screen management package.

       Available add-on packages including an interactive debugger, database,
       X-window graphics, BGI graphics, Motif, and Open-Windows packages.

       A compiler (HOBBIT, available separately) and dynamic linking of
       compiled modules.

       Setable levels of monitoring and timing information printed
       interactively (the `verbose' function).  Restart, quit, and exec.

FILES
       scm.texi
              Texinfo documentation of scm enhancements, internal
              representations, and how to extend or include scm in other
              programs.

AUTHORS
       Aubrey Jaffer (jaffer @ alum.mit.edu)
       Radey Shouman (shouman @ ne.mediaone.net)

BUGS
SEE ALSO
       The SCM home-page:
       http://swissnet.ai.mit.edu/~jaffer/SCM.html

       The Scheme specifications for details on specific procedures
       (http://swissnet.ai.mit.edu/ftpdir/scheme-reports/) or

       IEEE Std 1178-1990,
       IEEE Standard for the Scheme Programming Language,
       Institute of Electrical and Electronic Engineers, Inc.,
       New York, NY, 1991

       Brian Harvey and Matthew Wright
       Simply Scheme: Introducing Computer Science_
       MIT Press, 1994 ISBN 0-262-08226-8

       R. Kent Dybvig, The Scheme Programming Language,
       Prentice-Hall Inc, Englewood Cliffs, New Jersey 07632, USA

       H. Abelson, G. J. Sussman, and J. Sussman,
       Structure and Interpretation of Computer Programs,
       The MIT Press, Cambridge, Massachusetts, USA



4th Berkeley Distribution                                      SCM(Jan 4 2000)