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(guile-tut.info)What is libguile

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What is libguile
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  "Libguile" is the library which allows C programs to start a Scheme
interpreter and execute Scheme code.  There are also facilities in
libguile to make C data structures available to Scheme, and vice versa.

  The interface provided by the libguile C library is somewhat specific
to the implementation of the Scheme interpreter.  This low-level
libguile interface is usually referred to as the `scm_' interface,
since its public calls (API) all have the `scm_' prefix.

  There is also a higher-level libguile interface, which is usually
referred to as the `gh_' interface (libGuile High).  Its public calls
all have the `gh_' prefix.  The `gh_' library interface is designed to
hide the implementation details, thus making it easier to assimilate
and portable to other underlying Scheme implementations.

  People extending Guile by adding bindings to C libraries (like OpenGL
or Rx) are encouraged to use the `gh_' interface, so their work will be
portable to other Scheme systems.  The `gh_' interface should be more
stable, because it is simpler.

  The `scm_' interface is necessary if you want to poke into the
innards of Scheme data structures, or do anything else that is not
offered by the `gh_' interface.  It is not covered in this tutorial,
but is covered extensively in Note: Guile Reference Manual.


  This chapter gives a gentle introduction to the `gh_' interface,
presenting some _hello world_-style programs which I wrote while
teaching myself to use libguile.

  The `Guile Programmer's Manual' gives more examples of programs
written using libguile, illustrating diverse applications.  You can also
consult my _Gnudl_ documentation at
<http://nis-www.lanl.gov/~rosalia/mydocs/> to see a large scale project
that uses C and Scheme code together.