INTRO.DOC                                                November 1996


    INTRODUCTION:


    This document is intended for new users of the file archiver, JAR.

    JAR is a program that allows the user to store one or more files in a
    compressed format in an archive file.


    INSTALLATION:


    This assumes that you have already executed the self-extracting
    distribution archive and extracted its archived files into a directory.

    To install the JAR software, simply copy JAR16.EXE, JAR32.EXE, JAR.CFG,
    REARJ.EXE, REARJ.CFG and optionally JAR_C.COM and JAR_C.DLL (available
    in the non-export version only) to one of the directories named in your
    DOS PATH statement found in your AUTOEXEC.BAT. On many PCs, this
    directory may be C:\DOS or C:\BIN.

    In addition, for a DOS machine or for a DOS environment one MB of
    available XMS strongly recommended.  Four MB of EMS preferred for
    outstanding compression.  More memory is better.  Detailed information
    about memory usage is available in JAR.DOC in section "HOW JAR USES
    AVAILABLE MEMORY".


    JAR COMMAND USAGE:


    The JAR archiver gives you a lot of flexibility in command usage. You
    can use zero options or many options on a command line.

    The basic command line consists of:
    1) the command "JAR16" or "JAR32"
    2) the JAR command letter(s) such as "a" (add), or "e" (extract)
    3) the switch options such as "-r" (recurse through subdirectories)
    4) the name of the JAR archive
    5) the names of the selected files

    JAR16 <command> [<options>] <archive_name> [<files>]

    Switch options (-r, -hk, and so on) may be placed anywhere in the
    command line after the command "JAR16".  The default for the selected
    files is "*.*".

    To run the 32-bit JAR version (for Windows 95 and Windows NT) instead
    of the "JAR16" command you must specify "JAR32". "JAR32.EXE" is a
    32-bit executable which does not run in DOS but works in Windows 95 and
    Windows NT. "JAR32.EXE" is much faster and compresses better than the
    DOS version "JAR16.EXE".


    CREATING JAR ARCHIVES:


    To create an JAR archive containing all of the files in the current
    directory:

       JAR16 a archive

    To create an JAR archive in another directory containing all of the
    files in the current directory:

       JAR16 a directory\archive

    To create an JAR archive containing all files with the ".DOC" extension
    in the current directory:

       JAR16 a archive *.DOC

    To create an JAR archive containing all files with the ".DOC" and
    ".EXE" extension in the current directory:

       JAR16 a archive *.DOC *.EXE

    To create an JAR archive containing all of the files in a named
    directory:

       JAR16 a archive named\*.*

    To create an JAR archive containing all of the files in the named
    directory and all files in subdirectories of the named directory:

       JAR16 a -r archive named\*.*

    For maximum compression, use the "-m3" or "-m4" options. For better
    speed, use the -m1 option.

       JAR16 a -r -m4 archive named\*.*

    To use the 32-bit JAR version simply replace JAR16 with JAR32.


    LISTING THE CONTENTS OF AN ARCHIVE:


    To list all of the files in an archive:

       JAR16 l archive

    To list all of the files in short form:

       JAR16 ls archive

    It may be useful to redirect the listing to a file or pipe:

       JAR16 ls archive > archive.lst
       JAR16 ls archive | more

    To view only the files with a ".DOC" file extension in an archive:

       JAR16 v archive *.DOC


    EXTRACTING JAR ARCHIVES:


    To extract all of the files in an archive to the current directory:

       JAR16 e archive

    To extract all of the files in an archive to a named directory:

       JAR16 e archive -onamed

    To extract all files with the ".DOC" extension to the current
    directory:

       JAR16 e archive *.DOC

    To extract all of the files in an archive recreating the original
    directory structure:

       JAR16 x archive


    TESTING THE INTEGRITY OF AN ARCHIVE:


    To test the contents of an archive:

       JAR16 t archive

    This testing verifies that the contents of the archive data matches the
    original file. This is done using cyclical redundancy checksumming, CRC
    for short. JAR uses a 32 bit CRC for increased reliability.


    COMMON PROBLEMS USING JAR:


    By default, JAR stores the path specified with the filename in the
    archive.  "JAR16 a archive temp\*.*" will store the path "temp\" with
    the filenames. Another alternative is to store the RELATIVE path using
    the "-jf-" option.

    When updating an JAR archive, JAR builds the new archive as a temporary
    file in the same directory as the original archive. This can require a
    lot of extra disk space. If you are adding files, you will need as much
    free space as the original archive plus space for the added files.

    When archiving files to DISKETTES, it is STRONGLY recommended that you
    use the "-w" and "-hk" options.  The "-w" option sets a working
    directory.  This should point to a fast disk drive directory.  The
    "-hk" adds recovery records which will allow you to repair a slightly
    damaged archive (this is a common problem when using diskettes).  In
    addition, the "-jt" option may be used to test the created archive;
    however, this requires a re-read of all the diskettes.

    JAR16 a -wc:\ -hk a:archive *.*

    When copying archives to DISKETTES, it is strongly recommended that you
    verify that the diskette archives are intact.  Most damaged archives
    involve diskettes.


    FOR FURTHER STUDY:


    JAR supports a great number of options for functions such as archiving
    across multiple diskettes, accessing files with selected attributes,
    selecting files by date, and more. See the JAR.DOC reference guide for
    more information.


    end of document