### es-0.9.b1 README file

    This is the README file for es, version 0.9-beta1

    I include the original README file below.  See the CHANGES file for
    a list of changes to the shell.  See the INSTALL file for instructions
    for installing es.  In all other ways, I believe that this file is up
    to date.

    Soren Dayton
    csdayton@cs.uchicago.edu

    Es is an extensible shell.  The language was derived from the Plan 9
    shell, rc, and was influenced by functional programming languages,
    such as Scheme, and the Tcl embeddable programming language.  This
    implementation is derived from Byron Rakitzis's public domain
    implementation of rc.

    WARNING: This is an experimental release of es.  Some aspects of this
    	 release are unstable.  If you aren't feeling adventurous, you
    	 may want to use version 0.84.

    The Makefile should just work; if it doesn't, please let us know.  The
    first few lines include some comments about what might be problematic.
    Please see config.h for any conditional flags you may have to set on
    the command line to make es compile.  An ANSI C compiler is
    practically required.

    See the file CHANGES for recent changes to the shell.  For details on
    how to use es, please see the man page, which is unfortunately a bit
    out of date.  The file initial.es, which is used to build the initial
    memory state of the es interpreter, can be read to better understand
    how pieces of the shell interact.

    For some background into our motivation for writing es, see our Winter
    1993 Usenix paper, ``Es: a shell with higher-order functions,''
    available by anonymous ftp as

    	ftp.sys.utoronto.ca:/pub/es/usenix-w93.ps.Z

    The paper corresponds to a slightly older version of the shell;  see
    the file ERRATA for changes which affect parts of the paper.

    An old version of Paul's .esrc (es startup) file is provided as an
    example as esrc.haahr; correctness is not guaranteed.  A simple
    debugger for es scripts, esdebug, is also included; this is very
    untested and should be considered little more than a sketch of a few
    ideas.

    A simple history mechanism for this shell (conceptually derived from
    the Research Eighth Edition Unix =(1) commands) is available in

    	ftp.sys.utoronto.ca:/pub/es/history.tar.Z

    Es supports the use of GNU readline (or compatible) libraries for
    interactive command-line editing.  Readline may be obtained from any
    of the many GNU project distribution sites, such as prep.ai.mit.edu.
    Simi Turner wrote a much smaller readline clone called editline which
    Rich Salz has been maintaining; a copy of it is available as

    	ftp.sys.utoronto.ca:/pub/es/editline.tar.Z

    Please report any problems to us at

    	Paul Haahr <haahr@adobe.com>
    	Byron Rakitzis <byron@netapp.com>

    There is a mailing list for discussing es.  Send mail to

    	es-request@hawkwind.utcs.toronto.edu

    to join the list.  The list itself is

    	es@hawkwind.utcs.toronto.edu

    Es is in the public domain.  We hold no copyrights or patents on
    the source code, and do not place any restrictions on its distribution.
    We would appreciate it if any distributions do credit the authors.

    Enjoy!

    -- Paul Haahr & Byron Rakitzis