The SCM Implementation of Scheme

Current Version	Released	Terms
5f5	2026-08-06	LGPL

SCM is a Scheme implementation conforming to Revised⁵ Report on the Algorithmic Language Scheme and the IEEE P1178 specification^*. Scm is written in C and runs under Amiga, Atari-ST, GNU/Linux, MacOS, MS-DOS, MS-Vista, MS-Windows, OS/2, NOS/VE, Unicos, VMS, Unix and similar systems.

SCM includes Hobbit, the Scheme-to-C compiler originally written by Tanel Tammet. Hobbit generates C files whose binaries can be dynamically or statically linked with a SCM executable. SCM includes linkable modules for sequence-comparison, arrays, records, and byte-number conversions; and modules for POSIX system calls and network-sockets, readline, ncurses, and Xlib.

SCM requires the SLIB Scheme Library. Both SCM and SLIB are GNU packages.

News

scm-5f5 adds functions erf, erfc, log-gamma, real-gamma, exp-1, and log1+ if the C compiler supports C99.
scm-5f5 won't choke if a soft-port is used after transcript-off.

Quick Start

x86 MS-Windows

Obtain slib-3c2-1.exe (1.1.MB) and run.
Obtain older version scm-5f5-1.exe (475.kB) and run.
Release Notes:

The Windows installers were packaged by the NSIS (Nullsoft Scriptable Install System).
The SCM executable for MS-Windows was compiled by MSYS2
SCM.EXE supports WB B-Tree Databases with SCM.

i686 GNU/Linux with RPM

Obtain slib-3c2-1.noarch.rpm (760.kB) and scm-5f5-1.i686.rpm (960.kB) and install.

x86_64 GNU/Linux with RPM

Obtain slib-3c2-1.noarch.rpm (760.kB) and scm-5f5-1.x86_64.rpm (1.2.MB) and install.

Build From Source

Obtain the last release: slib-3c2.zip (1.1.MB) and scm-5f5.zip (920.kB)
or the current development snapshot: slib.zip (1.1.MB) and scm.zip (930.kB).
Follow the instructions in Installing SCM, chapter 2 of the SCM manual.

Documentation

Online SCM Manual; or scm.pdf
Online Xlibscm Manual; or Xlibscm.pdf
Online Hobbit Compiler Manual; or hobbit.pdf
Online SLIB Manual; or slib.pdf
Online Revised⁵ Report on the Algorithmic Language Scheme; or r5rs.pdf
HTML labyrinth of the build relational database generated by the command:
scm -r'db->html' -rbuild -e'(db->html-directory build "build")'

SCM Development

Savannah: CVS Repository scm/scm
Development Snapshot scm.zip (830.kB)
SCM discussion mailing list

Related Sites and Software

SLIB Scheme Library
WB B-Tree Databases for SCM.
SCM for Macintosh (original site)
Guile Universal Scripting Language
The #! program implements "#!" (POSIX) shell-scripts for MS-DOS batch files.
Fetch http://groups.csail.mit.edu/mac/ftpdir/scm/sharpbang.zip or http://groups.csail.mit.edu/mac/ftpdir/scm/#!.zip and unzip into a %PATH% directory.

Miscellany

About SCM Interpreter Speed
SCM Interpreter Latency
Using SCM in Engineering
FTP Links to SCM and related software from this site and mirrors.
htmls.zip, a collection of these html documentation files (600.kB)

I am a guest and not a member of the MIT Computer Science and Artificial Intelligence Laboratory. My actions and comments do not reflect in any way on MIT.
	agj @ alum.mit.edu	Go Figure!