This directory contains the distribution of scm5e7.  SCM conforms to
Revised^5 Report on the Algorithmic Language Scheme and the IEEE P1178
specification.  SCM runs under Amiga, Atari-ST, MacOS, MS-DOS, OS/2,
NOS/VE, Unicos, VMS, Unix and similar systems.  SCM supports the SLIB
Scheme library; both SCM and SLIB are GNU packages.

               `http://people.csail.mit.edu/jaffer/SCM'

0.1 Manifest
============

`.gdbinit'       provides commands for debugging SCM with GDB
`COPYING'        GNU GENERAL PUBLIC LICENSE
`COPYING.LESSER' GNU LESSER GENERAL PUBLIC LICENSE
`ChangeLog'      changes to SCM.
`Idiffer.scm'    Linear-space O(PN) sequence comparison.
`Iedline.scm'    Gnu readline input editing.
`Init.scm'       Scheme initialization.
`Link.scm'       Dynamic link/loading.
`Macro.scm'      Supports Syntax-Rules Macros.
`Makefile'       builds SCMLIT using the `make' program.
`QUICKREF'       Quick Reference card for R4RS and IEEE Scheme.
`README'         contains a MANIFEST, INSTALLATION INSTRUCTIONS, hints
                 for EDITING SCHEME CODE, and a TROUBLE SHOOTING GUIDE.
`Transcen.scm'   inexact builtin procedures.
`bench.scm'      computes and records performance statistics of pi.scm.
`build.bat'      invokes build.scm for MS-DOS
`build.scm'      database for compiling and linking new SCM programs.
`byte.c'         strings as bytes.
`bytenumb.c'     Byte-number conversions.
`compile.scm'    Hobbit compilation to C.
`continue-ia64.S'replaces make_root_continuation(), make_continuation(),
                 and dynthrow() in continue.c
`continue.c'     continuations.
`continue.h'     continuations.
`crs.c'          interactive terminal control.
`debug.c'        debugging, printing code.
`differ.c'       Linear-space O(PN) sequence comparison.
`dynl.c'         dynamically load object files.
`ecrt0.c'        discover the start of initialized data space
                 dynamically at runtime.
`edline.c'       Gnu readline input editing (get
                 ftp.sys.toronto.edu:/pub/rc/editline.shar).
`eval.c'         evaluator, apply, map, and foreach.
`example.scm'    example from R4RS which uses inexact numbers.
`fdl.texi'       GNU Free Documentation License.
`findexec.c'     find the executable file function.
`get-contoffset-ia64.c'makes contoffset-ia64.S for inclusion by continue-ia64.S
`gmalloc.c'      Gnu malloc(); used for unexec.
`gsubr.c'        make_gsubr for arbitrary (< 11) arguments to C
                 functions.
`ioext.c'        system calls in common between PC compilers and unix.
`lastfile.c'     find the point in data space between data and libraries.
`macos-config.h' Included by unexmacosx.c and lastfile.c.
`mkimpcat.scm'   build SCM-specific catalog for SLIB.
`patchlvl.h'     patchlevel of this release.
`pi.c'           computes digits of pi [cc -o pi pi.c;time pi 100 5].
`pi.scm'         computes digits of pi [type (pi 100 5)].  Test
                 performance against pi.c.
`posix.c'        posix library interface.
`pre-crt0.c'     loaded before crt0.o on machines which do not remap
                 part of the data space into text space in unexec.
`r4rstest.scm'   tests conformance with Scheme specifications.
`ramap.c'        array mapping
`record.c'       proposed `Record' user definable datatypes.
`repl.c'         error, read-eval-print loop, read, write and load.
`rgx.c'          string regular expression match.
`rope.c'         C interface functions.
`sc2.c'          procedures from R2RS and R3RS not in R4RS.
`scl.c'          inexact arithmetic
`scm.1'          unix style man page.
`scm.c'          initialization, interrupts, and non-IEEE utility
                 functions.
`scm.doc'        man page generated from scm.1.
`scm.h'          data type and external definitions of SCM.
`scm.texi'       SCM installation and use.
`scmfig.h'       contains system dependent definitions.
`scmmain.c'      initialization, interrupts, and non-IEEE utility
                 functions.
`script.c'       utilities for running as `#!' script.
`setjump.h'      continuations, stacks, and memory allocation.
`setjump.mar'    provides setjump and longjump which do not use $unwind
                 utility on VMS.
`setjump.s'      provides setjump and longjump for the Cray YMP.
`socket.c'       BSD socket interface.
`split.scm'      example use of crs.c.  Input, output, and diagnostic
                 output directed to separate windows.
`subr.c'         the rest of IEEE functions.
`sys.c'          call-with-current-continuation, opening and closing
                 files, storage allocation and garbage collection.
`time.c'         functions dealing with time.
`ugsetjump.s'    provides setjump and longjump which work on Ultrix VAX.
`unexalpha.c'    Convert a running program into an Alpha executable file.
`unexec.c'       Convert a running program into an executable file.
`unexelf.c'      Convert a running ELF program into an executable file.
`unexhp9k800.c'  Convert a running HP-UX program into an executable file.
`unexmacosx.c'   Convert a running program into an executable file under
                 MacOS X.
`unexsgi.c'      Convert a running program into an IRIX executable file.
`unexsunos4.c'   Convert a running program into an executable file.
`unif.c'         uniform vectors.
`unix.c'         non-posix system calls on unix systems.



File: scm-5e7.info,  Node: SLIB,  Next: Building SCM,  Prev: Making SCM,  Up: Installing SCM

2.2 SLIB
========

[SLIB] is a portable Scheme library meant to provide compatibility and
utility functions for all standard Scheme implementations.  Although
SLIB is not _neccessary_ to run SCM, I strongly suggest you obtain and
install it.  Bug reports about running SCM without SLIB have very low
priority.  SLIB is available from the same sites as SCM:

Unpack SLIB (`tar xzf slib-3b3.tar.gz' or `unzip -ao slib-3b3.zip') in
an appropriate directory for your system; both `tar' and `unzip' will
create the directory `slib'.

Then create a file `require.scm' in the SCM "implementation-vicinity"
(this is the same directory as where the file `Init5e7.scm' is
installed).  `require.scm' should have the contents:

     (define (library-vicinity) "/usr/local/lib/slib/")

where the pathname string `/usr/local/lib/slib/' is to be replaced by
the pathname into which you installed SLIB.  Absolute pathnames are
recommended here; if you use a relative pathname, SLIB can get confused
when the working directory is changed (*note chmod: I/O-Extensions.).
The way to specify a relative pathname is to append it to the
implementation-vicinity, which is absolute:

     (define library-vicinity
       (let ((lv (string-append (implementation-vicinity) "../slib/")))
         (lambda () lv)))

Alternatively, you can set the (shell) environment variable
`SCHEME_LIBRARY_PATH' to the pathname of the SLIB directory (*note
SCHEME_LIBRARY_PATH: SCM Variables.).  If set, the environment variable
overrides `require.scm'.  Again, absolute pathnames are recommended.



File: scm-5e7.info,  Node: Making SCM,  Next: SLIB,  Prev: Installing SCM,  Up: Installing SCM

2.1 Making SCM
==============

The SCM distribution has "Makefile" which contains rules for making
"scmlit", a "bare-bones" version of SCM sufficient for running `build'.
`build' is used to compile (or create scripts to compile) full featured
versions (*note Building SCM::).

Makefiles are not portable to the majority of platforms.  If `Makefile'
works for you, good; If not, I don't want to hear about it.  If you
need to compile SCM without build, there are several ways to proceed:

   * Use the build (http://people.csail.mit.edu/jaffer/buildscm.html)
     web page to create custom batch scripts for compiling SCM.

   * Use SCM on a different platform to run `build' to create a script
     to build SCM;

   * Use another implementation of Scheme to run `build' to create a
     script to build SCM;

   * Create your own script or `Makefile'.



File: scm-5e7.info,  Node: Editing Scheme Code,  Next: Debugging Scheme Code,  Prev: SCM Session,  Up: Operational Features

3.7 Editing Scheme Code
=======================

 -- Function: ed arg1 ...
     The value of the environment variable `EDITOR' (or just `ed' if it
     isn't defined) is invoked as a command with arguments ARG1 ....

 -- Function: ed filename
     If SCM is compiled under VMS `ed' will invoke the editor with a
     single the single argument FILENAME.

Gnu Emacs:
     Editing of Scheme code is supported by emacs.  Buffers holding
     files ending in .scm are automatically put into scheme-mode.

     If your Emacs can run a process in a buffer you can use the Emacs
     command `M-x run-scheme' with SCM.  Otherwise, use the emacs
     command `M-x suspend-emacs'; or see "other systems" below.

Epsilon (MS-DOS):
     There is lisp (and scheme) mode available by use of the package
     `LISP.E'.  It offers several different indentation formats.  With
     this package, buffers holding files ending in `.L', `.LSP', `.S',
     and `.SCM' (my modification) are automatically put into lisp-mode.

     It is possible to run a process in a buffer under Epsilon.  With
     Epsilon 5.0 the command line options `-e512 -m0' are neccessary to
     manage RAM properly.  It has been reported that when compiling SCM
     with Turbo C, you need to `#define NOSETBUF' for proper operation
     in a process buffer with Epsilon 5.0.

     One can also call out to an editor from SCM if RAM is at a
     premium; See "under other systems" below.

other systems:
     Define the environment variable `EDITOR' to be the name of the
     editing program you use.  The SCM procedure `(ed arg1 ...)' will
     invoke your editor and return to SCM when you exit the editor.  The
     following definition is convenient:

          (define (e) (ed "work.scm") (load "work.scm"))

     Typing `(e)' will invoke the editor with the file of interest.
     After editing, the modified file will be loaded.



File: scm-5e7.info,  Node: Problems Compiling,  Next: Problems Linking,  Prev: Automatic C Preprocessor Definitions,  Up: Installing SCM

2.8 Problems Compiling
======================

FILE    PROBLEM / MESSAGE                HOW TO FIX
*.c     include file not found.          Correct the status of
                                         STDC_HEADERS in scmfig.h.
                                         fix #include statement or add
                                         #define for system type to
                                         scmfig.h.
*.c     Function should return a value.  Ignore.
        Parameter is never used.         
        Condition is always false.       
        Unreachable code in function.    
scm.c   assignment between incompatible  Change SIGRETTYPE in scm.c.
        types.                           
time.c  CLK_TCK redefined.               incompatablility between
                                         <stdlib.h> and <sys/types.h>.
                                         Remove STDC_HEADERS in scmfig.h.
                                         Edit <sys/types.h> to remove
                                         incompatability.
subr.c  Possibly incorrect assignment    Ignore.
        in function lgcd.                
sys.c   statement not reached.           Ignore.
        constant in conditional          
        expression.                      
sys.c   undeclared, outside of           #undef STDC_HEADERS in scmfig.h.
        functions.                       
scl.c   syntax error.                    #define SYSTNAME to your system
                                         type in scl.c (softtype).



File: scm-5e7.info,  Node: Problems Linking,  Next: Problems Running,  Prev: Problems Compiling,  Up: Installing SCM

2.9 Problems Linking
====================

PROBLEM                              HOW TO FIX
_sin etc. missing.                   Uncomment LIBS in makefile.



File: scm-5e7.info,  Node: Problems Running,  Next: Testing,  Prev: Problems Linking,  Up: Installing SCM

2.10 Problems Running
=====================

PROBLEM                              HOW TO FIX
Opening message and then machine     Change memory model option to C
crashes.                             compiler (or makefile).
                                     Make sure sizet definition is
                                     correct in scmfig.h.
                                     Reduce the size of HEAP_SEG_SIZE in
                                     setjump.h.
Input hangs.                         #define NOSETBUF
ERROR: heap: need larger initial.    Increase initial heap allocation
                                     using -a<kb> or INIT_HEAP_SIZE.
ERROR: Could not allocate.           Check sizet definition.
                                     Use 32 bit compiler mode.
                                     Don't try to run as subproccess.
remove <FLAG> in scmfig.h and        Do so and recompile files.
recompile scm.                       
add <FLAG> in scmfig.h and           
recompile scm.                       
ERROR: Init5e7.scm not found.        Assign correct IMPLINIT in makefile
                                     or scmfig.h.
                                     Define environment variable
                                     SCM_INIT_PATH to be the full
                                     pathname of Init5e7.scm.
WARNING: require.scm not found.      Define environment variable
                                     SCHEME_LIBRARY_PATH to be the full
                                     pathname of the scheme library
                                     [SLIB].
                                     Change library-vicinity in
                                     Init5e7.scm to point to library or
                                     remove.
                                     Make sure the value of
                                     (library-vicinity) has a trailing
                                     file separator (like / or \).



File: scm-5e7.info,  Node: Testing,  Next: Reporting Problems,  Prev: Problems Running,  Up: Installing SCM

2.11 Testing
============

Loading `r4rstest.scm' in the distribution will run an [R4RS]
conformance test on `scm'.

     > (load "r4rstest.scm")
     -|
     ;loading "r4rstest.scm"
     SECTION(2 1)
     SECTION(3 4)
      #<primitive-procedure boolean?>
         #<primitive-procedure char?>
            #<primitive-procedure null?>
               #<primitive-procedure number?>
     ...

Loading `pi.scm' in the distribution will enable you to compute digits
of pi.

     > (load "pi")
     ;loading "pi"
     ;done loading "pi.scm"
     ;Evaluation took 20 ms (0 in gc) 767 cells work, 233.B other
     #<unspecified>
     > (pi 100 5)
     00003 14159 26535 89793 23846 26433 83279 50288 41971 69399
     37510 58209 74944 59230 78164 06286 20899 86280 34825 34211
     70679
     ;Evaluation took 550 ms (60 in gc) 36976 cells work, 1548.B other
     #<unspecified>

Loading `bench.scm' will compute and display performance statistics of
SCM running `pi.scm'.  `make bench' or `make benchlit' appends the
performance report to the file `BenchLog', facilitating tracking
effects of changes to SCM on performance.

PROBLEM                              HOW TO FIX
Runs some and then machine crashes.  See above under machine crashes.
Runs some and then ERROR: ...        Remove optimization option to C
(after a GC has happened).           compiler and recompile.
                                     #define SHORT_ALIGN in `scmfig.h'.
Some symbol names print incorrectly. Change memory model option to C
                                     compiler (or makefile).
                                     Check that HEAP_SEG_SIZE fits
                                     within sizet.
                                     Increase size of HEAP_SEG_SIZE (or
                                     INIT_HEAP_SIZE if it is smaller
                                     than HEAP_SEG_SIZE).
ERROR: Rogue pointer in Heap.        See above under machine crashes.
Newlines don't appear correctly in   Check file mode (define OPEN_... in
output files.                        `Init5e7.scm').
Spaces or control characters appear  Check character defines in
in symbol names.                     `scmfig.h'.
Negative numbers turn positive.      Check SRS in `scmfig.h'.
;ERROR: bignum: numerical overflow   Increase NUMDIGS_MAX in `scmfig.h'
                                     and recompile.
VMS: Couldn't unwind stack.          #define CHEAP_CONTINUATIONS in
                                     `scmfig.h'.
VAX: botched longjmp.                

Sparc(SUN-4) heap is growing out of control
     You are experiencing a GC problem peculiar to the Sparc.  The
     problem is that SCM doesn't know how to clear register windows.
     Every location which is not reused still gets marked at GC time.
     This causes lots of stuff which should be collected to not be.
     This will be a problem with any _conservative_ GC until we find
     what instruction will clear the register windows.  This problem is
     exacerbated by using lots of call-with-current-continuations.  A
     possible fix for dynthrow() is commented out in `continue.c'.

