---
name: "bchscheme"
section: "1"
platform: "linux"
package: "mit-scheme"
version: "7.7.90+20060906-3"
release: "Debian 4.0 (Etch)"
platforms: ["linux"]
url: "https://new.carta.tech/mit-scheme"
---

# bchscheme(1)

Scheme development environment

Part of [mit-scheme(1)](/mit-scheme/1.md).

## NAME

MIT/GNU Scheme - Scheme development environment

## SYNOPSIS

**mit-scheme** \[*OPTIONS*\]\
 **bchscheme** \[*OPTIONS*\]\

## DESCRIPTION

MIT/GNU Scheme is an implementation of the Scheme programming language, providing an interpreter, compiler, source-code debugger, integrated Emacs-like editor, and a large runtime library.  MIT/GNU Scheme is best suited to programming large applications with a rapid development cycle.

There are two executable programs.  The programs are functionally identical, but use different garbage collectors. The **mit-scheme** program uses a standard two-space copying garbage collector.  This optimizes performance but uses a lot of memory.  The **bchscheme** program uses a special two-space copying garbage collector with one heap in memory and the other on the disk.  This makes garbage collection slower but uses less memory.

## OPTIONS

These are some of the more common command-line options.  For full information about available options, see the Texinfo documentation.

- \--compiler

  Load the native-code compiler.

- \--edwin

  Load the Emacs-like text editor.

- \--heap *NBLOCKS*

  Specify the size of the heap in 1024-word blocks. The default heap size is 1000 blocks if either --compiler or --edwin is specified, and 250 blocks otherwise.

- \--stack *NBLOCKS*

  Specify the size of the stack in 1024-word blocks. The default stack size is 100 blocks.

- \--library *PATH*

  Specify where to look for Scheme's binary files. *PATH* should be a colon-separated list of directory names.

- \--no-init-file

  Don't load the user's init file.

- \--edit

  Start the text editor automatically.  Meaningful only when combined with the --edwin option.

- \--eval *EXPRESSION*...

  Evaluate the specified expressions after starting Scheme.

- \--load *FILENAME*...

  Load the specified files after starting Scheme.

- \--option-summary

  Print a summary of the command-line options, including default values.

## FILES

*/usr/lib/mit-scheme*

## ENVIRONMENT VARIABLES

MIT/GNU Scheme refers to a large number of environment variables.  See the Texinfo documentation for details.

## EXAMPLES

To use the interpreter without any frills, type:

**mit-scheme**

To also load the compiler, type:

**mit-scheme** --compiler

To load the compiler and editor, type:

**mit-scheme** --compiler --edwin --edit

## AUTHORS

MIT/GNU Scheme Team \<bug-mit-scheme@gnu.org\>

## SEE ALSO

The full documentation for MIT/GNU Scheme is maintained as a set of Texinfo manuals. If the **info** program is properly installed at your site, the command

-

  **info** "MIT/GNU Scheme User"

should give you access to the complete User's manual.  Programming information is located in the Info topics "MIT/GNU Scheme Ref" and "SOS".  Usage of the **IMAIL** mail reader is located in the "IMAIL" topic.