Subject: comp.sys.mac.comm Frequently Asked Questions [1/4]
Date: 9 Jan 1996 00:53:59 GMT
Summary: This is the comp.sys.mac.comm Frequently Asked Questions list; its
. intent is to provide information specific to Macintosh computer
. communications, including modems, networks, and the like. You are
. encouraged to read this FAQ before posting to the newsgroup.

Archive-name: macintosh/comm-faq/part1
Last-modified: Mon Jan  8 1995

This is the Frequently Asked Questions (FAQ) list for comp.sys.mac.comm
=======================================================================

This list of frequently asked questions and answers is intended to help
reduce the number of "often asked questions" that make the rounds here
in comp.sys.mac.comm. Since comp.sys.mac.comm is intended as a forum to
discuss telecommunication (and related issues) that are specific to the
Macintosh, most questions about modems, telecommunications in general,
and other non-Macintosh specific communication questions are not listed
here. The proper newsgroup for such questions is usually comp.dcom.modems.

This list is posted periodically (about once a month) to the Usenet 
groups comp.sys.mac.comm, news.answers, and comp.answers. Latest versions
of the FAQ can be retrieved via anonymous FTP from the following sites:

file://mac.archive.umich.edu/mac/misc/documentation/compsysmaccommfaq.txt

file://sumex-aim.stanford.edu/info-mac/comm/info/comp-sys-mac-comm-faq.txt

file://rtfm.mit.edu/pub/usenet/comp.sys.mac.comm/c.s.m.c_FAQ_[1_4]
                                                 c.s.m.c_FAQ_[2_4]
                                                 c.s.m.c_FAQ_[3_4]
                                                 c.s.m.c_FAQ_[4_4]

It also available in the Macintosh SIG on Delphi for Delphi members.

This FAQ is purely a volunteer effort. Although every effort has been
made to insure that answers are as complete and accurate as possible,
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at csmc-faq@phoenix.Princeton.EDU.

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.
================================================================================

                          **** TABLE OF CONTENTS: ****

[1] Modems and Cables

.[1.1] What kind of modem will work with my Macintosh?
.[1.2] What kind of cable do I need to use my external modem with my
.      Macintosh? (Includes cable pinouts)
.[1.3] What do V.32, V.42, bis, MNP, etc mean? 
.[1.4] How fast can the Macintosh serial ports really go?
.[1.5] How can I disable call-waiting when using my modem?

[2] File Formats and Conversion

.[2.1] What is a resource (or data) fork?
.[2.2] What is MacBinary?
.[2.3] What is BinHex? What is uuencode? What are atob/btoa ?
.[2.4] What is Apple-Single/Double ?
.[2.5] What do file suffixes like .hqx, .sit, .bin, etc ... mean
.      and how can I convert such files back to normal Macintosh
.      applications and documents?
.[2.6] How can I use a binary-downloaded file that appears as an
.      unusable text file on the Mac desktop?

[3] Macintosh File Transfers

.[3.1] What program(s) do(es) Kermit, FTP (client), and/or
.      X,Y,Z-MODEM and where can I get them?
.[3.2] What is the latest version of ZTerm? How can I find out more
..about ZTerm?
.[3.3] What is the Communications Toolbox (CTB)?
.[3.4] Are there any public-domain or shareware Communication
.      Toolbox tools that support Kermit, and/or X,Y,Z-MODEM?
.[3.5] How can I transfer Macintosh files to/from my Macintosh and
.      other non-Macintosh computers (eg: mainframes, UNIX boxes,
.      PCs)?
.[3.6] What's the best compression program to use when uploading
.      files to an archive or BBS? Are there any other guidelines
.      I should follow?
.[3.7] How can I use the programs that are posted to 
.      comp.binaries.mac?

[4] Introduction to AppleTalk (and Apple Remote Access)

.[4.1] What kind of hardware do I need to set up an LocalTalk
.      network?
.[4.2] How can I change the Chooser "user" and name of my
.      Macintosh? Also: Why can I no longer change the name of
.      my hard-disk?
.[4.3] What is Apple Remote Access?
.[4.4] Where can I get a Remote Access script for my modem? 
.[4.5] How can I use Apple Remote Access Client 2.0 as an ARA server?
.[4.6] How are IP packets transmitted over a LocalTalk network?
.[4.7] How can I use Apple Remote Access to access the Internet via my
..Mac at work?
.[4.8] How can I use the services of my EtherTalk network and print
..to my LocalTalk-only printer at the same time?
.[4.9] Is it possible to use AppleTalk over a TCP/IP network?

[5] TCP/IP Networking, MacTCP, Telnet, SLIP, PPP

.[5.1] What is MacTCP and what kind of hardware and software do I
.      need to use it? 
.[5.2] What is the difference between AppleTalk, LocalTalk,
.      Ethernet, EtherTalk, TCP/IP, etc?
.[5.3] What is Telnet, and is there a Telnet program for the
.      Macintosh?
.[5.4] Is there a FTP (client/server) program for the Macintosh?
.[5.5] What are SLIP, CSLIP and PPP?
.[5.6] What is the difference between SLIP and PPP?
.[5.7] MacPPP Frequently Asked Questions
.[5.8] How does MacTCP resolve names into IP addresses?
.[5.9] Is there a version of traceroute available for the Mac?
.[5.10] What Domain Name Server programs are available for the Mac?

[6] MacX and Other Ways to Interface With UNIX

.[6.1] Can I run X-Windows on my Mac?
.[6.2] How can I run MacX over a modem? Is it feasible?
.[6.3] What is MacLayers and what do I need to use it?
.[6.4] What are UW and MultiSession? Are there other programs like 
.      MacLayers?
.[6.5] Is there a UNIX program that will convert between BinHex and
.      MacBinary?
.[6.6] How can I create LaserWriter PostScript printer files and
.      print them on a PostScript printer connected to a UNIX
.      network?
.[6.7] How can I print over the network to a QuickDraw printer which 
.      doesn't support PostScript but is connected to a Macintosh?
        [6.8] What is the Columbia AppleTalk Package (CAP)?
        [6.9] How can I use the UNIX NFS file sharing protocol on my Mac?

[7] Sending and receiving mail and USENET news with your Macintosh

.[7.1] How can I send/receive Internet mail with my Macintosh?
.[7.2] How can I read/post Usenet news with my Macintosh?

[8] Miscellaneous

.[8.1] I don't have FTP --- How can I access the various archives
.      through e-mail?
.[8.2] What aids are available for programmers wishing to write TCP/IP
.      applications for the Macintosh?
.[8.3] I have a FAX machine and a FAX modem. How can I use these
.      devices together to emulate a scanner and a printer?

Appendices:

[A].List of Common File Suffixes and Abbreviations
[B].List of Macintosh archive sites available through the Internet
[C].Vendor Information
[D].Contributors
.
================================================================================

[1] Modems and Cables
=====================

[1.1] What kind of modem will work with my Macintosh?
-----------------------------------------------------

        Any *external* Hayes compatible modem will work with your
        Macintosh. There are too many to list or review here. The
        USENET newsgroup comp.dcom.modems is a good place to ask questions
        about the many different external Hayes compatible modems. Such
        modems can be used with any computer (Macintosh, UNIX box,
        MS-DOS PC, Amiga, etc) with a serial port (e.g.: Macintosh modem
        port) interface. However, there *are* modems that are designed
        specifically for use with the Macintosh. Internal Powerbook
        modems, ADB modems, and internal NuBus modems are all examples.

.Note that modems for the Macintosh Performa apparently can only
.plug into the Macintosh Performa because of an extra pin which
.they posesses (there is a corresponding extra hole on the Performa
.serial port connector into which this pin fits). As a result,
.the bundled Global Village FAX modem can only plug into the Performa. 
.Other modems can of course also plug into the Performa; the extra
.pin only prevents plugging the Performa-specific modem into other
.Macs.

        Assuming you wish to use an external modem, your only other
        hardware consideration is to find an appropriate cable to connect
        it to your Macintosh. Especially at higher bps rates (9600 bps
        and up), a hardware-handshaking cable is recommended (see [1.2]
        for details). There are many non-hardware-handshaking cables
        being sold at reputable computer accessory stores, so it's
        recommended that you ask before buying.

        Various special modems exist with unique features; the most
        notable type is the dual FAX/modem. For more information,
        visit comp.dcom.modems or your local dealer: there are simply
        too many products to describe here.


[1.2] What kind of cable do I need to use my external modem with my Macintosh?
------------------------------------------------------------------------------ 

        Most modems have a female DB-25 (25 pin) connector labelled
        RS-232C on their backsides. All Macintoshes since the Mac Plus
        use a mini DIN-8 (8 pin) connector for the two serial ports
        (modem and printer). Earlier models use the larger DB-9 (9 pin)
        connector. Finding a generic cable for any configuration should
        not be very difficult at most computer accessory stores. They
        are typically sold for around $25.

        However, especially at the higher bps rates (9600 bps and up),
        a hardware handshaking cable is highly recommended. Attempting
        to transfer files at high bps rates using a non-hardware-
        handshaking cable will likely result in repeated transmission
        errors, a drop in the transfer rate, and possibly an aborted
        transmission. Since many non-hardware-handshaking cables are
        still being sold, it's a good idea to ask before buying.

.One hardware handshaking cable available by mail-order is the
.CompUnite High-Speed Mac modem cable, available for $14 (as of 
.8/94) from Celestin Company (see the end of Part 4 of this FAQ 
.for vendor information). This product has been listed as a BMUG 
.(Berkeley, California Macintosh User's Group) Choice Product.

        If you want to "roll-your-own" or are having problems getting
        your modem and your Macintosh to communicate, read on. The
        serial ports on the Macintosh are not actually RS-232C ports
        but are instead RS-422 compliant, a similar but better standard.
        This explains some of the difficulty in implementing hardware-
        handshaking.

        One way to wire your cable is as below:

                Macintosh (DTE)                           Modem (DCE)
                    DIN-8                                    DB-25

                Pin  Signal                               Signal  Pin
                 1    HSKo   ---------------------------   RTS     4
                 2    HSKi   ---------------------------   CTS     5
                 3    TxD-   ---------------------------   TxD     2
                 4    GND    ---------------------------   GND     7
                 5    RxD-   ---------------------------   RxD     3
                 6    TxD+   (nc)                    .--   DSR     6
                 7    GPi    (nc)                    '--   DTR    20 
                 8    RxD+   ---------------------------   GND     7  

                    shield   ---------------------------   shield

                                Figure 1.2.1

        If your modem cannot be configured to ignore DTR, or if you
        are using an old 1200 bps or 2400 bps modem, the pinout in
        Figure 1.2.1 is probably best. However, if you are using a
        high-speed modem that can ignore DTR, and/or Remote AppleTalk,
        you should instead use the pinout in Figure 1.2.2, which is
        the pinout "recommended" by Apple:

                Macintosh (DTE)                           Modem (DCE)
                    DIN-8                                    DB-25

                Pin  Signal                               Signal  Pin
                 1    HSKo   ----------------------+----   RTS     4
                                                   '----   DTR    20

                 2    HSKi   ---------------------------   CTS     5
                 3    TxD-   ---------------------------   TxD     2

                 4    GND    ----+----------------------   GND     7
                 8    RxD+   ----'

                 5    RxD-   ---------------------------   RxD     3
                 6    TxD+   (nc)                    
                 7    GPi    ---------------------------   DCD     8

                    shield   ---------------------------   shield

                                Figure 1.2.2

        Note: You can find a pretty picture of this PICT by using 
        ResEdit to open the Apple Modem Tool Extension CTB tool.

        Note: Be careful! Although technically, you should not be able
        to damage either your modem or computer by using an incorrectly
        wired cable, you should always perform a connectivity test to
        double-check your wiring before using your homemade cable.
        Some serial devices place auxiliary voltages on non-standard
        pins.
        
        Note: If you are having trouble finding or soldering a mini DIN-8
        connector (they can be expensive and are rather small), it is
        suggested you purchase a straight-through DIN-8 to DIN-8 cable
        (often sold for use with serial port switches), cut it in half,
        and wire each end to a DB-25 connector that can plug into your
        modem (resulting in *two* cables).

.Note: The GPi pin is connected on almost all Macs (exceptions
.include the Mac Plus and Mac LC). Most software does not use this
.pin, however.

        Note: If you are running A/UX and are having difficulties
        controlling your modem from software, see the comp.unix.aux FAQ
        for the latest information on an A/UX specific cable.


        Many people routinely ask for a pinout diagram for the mini DIN-8
        connector; Figure 1.2.3 shows the pinout as if you were looking at
        the (female) connector on your Macintosh; the (male) cable connector
        will be a mirror image. (Figure artwork by Ben Cranston)

                     Mini DIN-8 Macintosh Serial Connector Pinout
 
               /------###------\         1 HSKo        Output Handshake
             /        ###        \                      (Zilog 8530 DTR pin)
           /                       \     2 HSKi/CLK    Input Handshake *OR*
          /     [|]   [|]   [|]     \                   External Clock
         /       8     7     6       \   3 TxD-        Transmit data (-)
        |                             |
        |                             |  4 Ground      Signal ground
        |     ===       ===    ===    |
        |      5         4      3     |  5 RxD-        Receive data (-)
        |                             |
        |                             |  6 TxD+        Transmit data (+)
         \----+    ===   ===    +----/
          \###|     2     1     |###/    7 N/C         (no connection)
           \##|                 |##/
             \|                 |/       8 RxD+        Receive data (+)
               \------###------/
                      ###

                                Figure 1.2.3
 
         Finally, it should be noted that there is no *best* RS-422 to
         RS-232 cable. You'll see many different wiring diagrams posted
         to Usenet. Each usually has its own purpose and champion; the
         two given in this FAQ, however, are fairly generic and one or
         the other should work with most modems being sold today.


[1.3] What do V.32, V.42, bis, MNP, etc mean?
---------------------------------------------

        Because these topics are universal telecommunications issues,
        they are more fully discussed in comp.dcom.modems. However, a
        short description of some of the more common abbreviations and
        buzzwords is given below.

        An excellent article on the subject of modems, including
        a guide to buying high-speed modems, is available from
        InfoMac (sumex-aim) and its mirror sites as the file
        info-mac/comm/info/modem-guide-11.hqx.
        
           Buzzword         What it typically means
        ---------------   ----------------------------------------------
        bit             : binary digit; amount of information necessary
                          to distinguish between two equally likely
                          events (such as the value of a binary digit)
        byte            : eight bits; size of a single ASCII character
        bps             : bits per second
        baud            : one analog signal state change; people usually
                          use baud and bps interchangeable, although most
                          modern modems can encode multiple bits per baud
        Bell 103        : 300 bps U.S. Standard
        Bell 212A       : 1200 bps U.S. Standard
        LAP/M           : Link Access Protocol/Modem.
        MNP             : Microcom Networking Protocol (Proprietary)
        MNP5            : MNP extension; 2 to 1 data compression.
        V.32            : 9600bps, 4800bps
        V.32bis         : 14.4Kbps, 12Kbps, 9600bps, 7200bps, 4800bps
        V.32terbo       : psuedo-standard extending V.32bis to 16.8, 19.2 kbs
        V.34            : 28,800 bps, 14,400 bps, 9,600 bps, 2,400 bps
        V.Fast          : Interim version of V.34; sometimes used as a nickname 
...  for V.34
        V.FC            : A proprietary Rockwell protocol used before V.34 was
...  approved as a standard
        V.42            : MNP 4 and LAP/M modem to modem error correction
        V.42bis         : LAP/M and 4-to-1 data compression.

.Note: Some V.FC modems do not work with V.34 modems at 28,800 bps.

.[FAX standards:]

        V.21            : 300 bps FAX
        V.27ter         : 4800 bps FAX
        V.29            : 9600 bps FAX
        V.17            : 14400 bps FAX


                             Table 1.3.1


[1.4] How fast can the Macintosh serial ports really go?
--------------------------------------------------------

        The Macintosh operating system supports data rates up to 57600 bps,
        but the Macintosh serial hardware can support transfer rates that
        are much higher if they are externally clocked. Serial port
        sound-input-devices such as the Cedar Technologies SID and
        Farallon's MacRecorder, as well as AppleTalk boxes, use this trick
        to achieve transfer rates greater than 100 Kbps.

Ward McFarland <70240.504@compuserve.com> writes:

."The clock rate supplied by pre-AV Macs to the SCC (and used for bps 
.rate generation) limits the maximum asynchronous serial speed to 
.57,600 bps. The maximum synchronous speed is 16 times this (as used 
.by the old serial hard drives used on 512K Macs and by the Personal 
.LaserWriters).

.Indeed, the SCC can be externally clocked to faster asynchronous 
.speeds, with a couple of limitiations.  First, the external clock
.is applied to the Mac's CTS input, making it impossible to respond 
.normally to normal modem handshake requests.  Second, since the SCC 
.used in older Macs can only buffer 3 characters, data losses can occur
.due to interrupt service delays. MacRecorder and other custom devices 
.got around this by locking out all system interrupts during serial 
.data transfer.

.The AVs and PowerMacs apparently use a different SCC clock, and I have
.benchmarked fairly good ZModem performance using Smartcom II 4.0 at 
.115,200 and 230,400 bps.  Apple does not publish the serial driver 
.control call to set this, and they state they do not support such
.speeds.  I do not know of anyone besides Hayes who has managed to get 
.Apple to tell them the methodology.

.Creative Solutions, Inc. [see the end of Part 4 of this FAQ for vendor
.contact information] makes a NuBus card (the "Hustler") and soon will
.make an external SCSI-based device that can support 2 channels at 
.115,200 bps or one at 230,400 bps.  This is currently used by quite 
.a number of people supporting high speed (28.8) modems and direct 
.serial connections. This product works fine with existing 
.communications and bulletin board system software."
        
        Note: Powerbooks are known to have problems at extremely high
        data rates. These problems are caused by Power Manager overhead.
        System 7.1 is supposed to solve or alleviate these problems.

        Note: AppleTalk being active can degrade serial port performance,
        as can Ethernet-network traffic. Turning off AppleTalk via
        the Chooser, or disconnecting the Ethernet transceiver, are
        work-arounds.

Dan Schwarz <Dan_Schwarz/Iris.IRIS@iris.com> adds

.AVs and PowerMacs use a newer SCC chip and a DMA based serial driver
.that can handle a much higher async throughput than the older,
.interrupt-based driver. 

.My SerialSpeed 230 control panel takes advantage of this new driver
.and allows many older applications to operate at speeds of 115,000bps
.or 230,000bps on the PowerMac and AV Mac. It's shareware and is widely
.available. 

.You can get a copy from the info-mac ftp site, or try 
.http://www.infohaus.com/access/by-seller/Brookline_Software
.The current (as of 30 May 1995) version is 1.2.

        
[1.5] How can I disable call-waiting when using my modem?
---------------------------------------------------------

        This varies depending on your local phone company, but often,
        if you preced the phone number you wish to tone dial
        with "*70," (omit the quotes but not the comma), you can
        disable call-waiting FOR THAT CALL ONLY.
        
        If you have a strictly rotary dial line, try preceding the
        phone number with "1170".

        In the United Kingdom, the code to use is #43#.

.In New Zealand, the code to use is *52.

.If you are using Telecom Australia, 
.ATDT#43#,;H     Will turn call-waiting OFF
.ATDT*43#,;H     Will turn it back ON again.

.
================================================================================
[2] File Formats and Conversion
===============================

[2.1] What is a resource (or data) fork?
----------------------------------------

        A Macintosh file has two parts: a data fork and a resource fork.
        Text files and GIF image files are examples of Macintosh files
        that are usually stored completely in the data fork, and have
        an empty (or nonexistent) resource fork. Applications, as a
        a counter-example, store most if not all of their information
        in 'resources' in the resource fork and usually have an empty
        data fork.
        
        Because this two-forked organization of files isn't very common,
        transferring Macintosh files that have non-empty resource forks
        to non-Macintosh machines (such as UNIX boxes, or MS-DOS machines)
        requires special encoding, described below.


[2.2] What is MacBinary?
------------------------

        MacBinary is a standard way of taking a Macintosh file (both
        resource and data forks) and creating a new file with just
        a data fork. This new file can then be transferred through
        machines which know nothing about the native Macintosh file
        system, without losing the information stored in the resource
        fork.
        
        MacBinary also stores other information (such as the filename,
        creation and modification dates, file type and creator) about
        the original file.
        
        If you want to store some Macintosh files on a non-Macintosh
        computer, one way is to convert them to a MacBinary format file
        before transferring. Note that MacBinary files are useless to
        people who are not using Macintosh computers. MacBinary's
        purpose is to encapsulate *all* information contained in a
        Macintosh file for transport over a non-Macintosh medium. For
        this reason, you should not use MacBinary and/or BinHex to
        post GIF images, for example, to Usenet because (1) GIF images
        contain no Macintosh specific information and (2) doing so will
        make it impossible for most non-Macintosh users to display your
        image.

        Although a Macintosh program (called MacBinary) does exist
        to do the converting to and from MacBinary, almost all modern
        Macintosh telecommunications programs have the capability of
        converting and unconverting MacBinary files for you. ZTerm,
        for example, can be configured to automatically detect when
        a MacBinary file is being received and to convert this file
        to its original representation; or, if you are uploading,
        ZTerm can optionally encode the file into MacBinary before
        sending. Fetch, White Knight, and most other commercial and
        shareware products have equivalent or similar capabilities.
        
.Dennis Brothers, Yves Lempereur, and others gathered on
.CompuServe to discuss what eventually became the original
.MacBinary standard. According to Lempereur, "We finally
.agreed on using the MacTerminal format (without the modified
.XModem protocol). I then wrote BinHex 5.0 (see [2.3]) to
.support MacBinary. A year later, the same group got together
.on CompuServe again and created MacBinary II."

.Since then, BinHex and the new MacBinary have become the
.standard way of encapsulating Macintosh files for transfer
.over foreign systems throughout the Internet, USENET, and
.elsewhere.

        MacBinary I is the name given to the old MacBinary standard.
        MacBinary II is the name given to the new MacBinary standard
        which everybody uses today; in common usage, MacBinary means
        MacBinary II.
        
        
[2.3] (a) What is BinHex? (b) What is uuencode? (c) What are atob/btoa ?
------------------------------------------------------------------------

        (a) A "binary" file is usually intended to describe a file which
        does not always have the high bit in each byte set to zero.
        Text and BinHex files are the most common examples of non-binary
        data. Programs and images are common examples of binary data.
        MacBinary files are specially encoded binary files (see 2.2]).
        
        Unfortunately, many network e-mail and Usenet gateways are only
        receptive to non-binary files. To make it possible to send
        binary files such as Macintosh MacBinary files through e-mail
        or Usenet, it is necessary to convert these files to a text-
        compatible form. BinHex and uuencode are two different ways
        of doing this. Both BinHex and uuencode result in files that
        are larger than the original binary version.
                
        BinHex 4.0, by Yves Lempereur, is a binary to text translator
        that can directly encode any Macintosh document (ie: it knows
        how to convert information in both the resource and data forks).
        BinHex files can be easily recognized since they begin with the
        line:
        
                (This file must be converted with BinHex 4.0)
        
        and are followed by a line starting with a colon, ':'. The
        BinHex encoding of the file follows, and is ended with another
        colon.
        
        There is in fact a program called "BinHex 4.0" in various
        archives, but you don't have to use it to convert files to and
        from BinHex. It's best to use one
        of the other more powerful utilities, such as HQXer, DeHqx,
        StuffIt Expander and other StuffIt programs, and Compact Pro,
        to name only a few. UNIX utilities (see [6.5]) that manipulate 
        BinHex, MacBinary, and other types of Macintosh files are also 
        available. StuffIt Expander has the advantage of also being able 
        to automatically expand StuffIt, Compact Pro, and Applelink 
        archives. Note that BinHex 4.0 has a bug wherein it refuses to
.decode .hqx files with very long names.

        Just about every Macintosh program posted appears as a BinHex
        archive. Some Macintosh archives also store their files in BinHex
        to allow users who don't have (or forget to use) binary mode in
        FTP to succesfully transfer files. 

        BinHex files are denoted by the suffix ".hqx". The specifications
        to BinHex, should you be an interested programmer, are available
        at the University of Michigan's Macintosh archive site as
        mac/misc/documentation/binhex4.0specs.txt, or at InfoMac sites 
        as dev/info/binhex-40-specs.txt .

        There is also a program/format called "BinHex 5.0"; it is NOT
        a more advanced version of "BinHex 4.0" but rather a separate
        _binary_ format (it uses the entire eight-bit ASCII character
        set and is thus not suitable for news postings or e-mail)
        (see [2.2]) BinHex 5.0, written by Yves Lempereur, was the
.first MacBinary converter available. Converting
        a file with BinHex 5.0 and then using BinHex 4.0 is another way
        of converting a native Macintosh files with data and resource
        forks into a format that can be e-mailed or posted (and then
        reconstructed). MacBinary, however, is almost always used in
        preference to BinHex 5.0.

.As new versions of BinHex were developed, they encoded only the
.new format but continued to decode all previous formats:

.BinHex 1.0 encodes .hex and decodes .hex
.BinHex 2.0 encodes .hex & .hcx and decodes .hex & .hcx
.BinHex 3.0 never existed
.BinHex 4.0 encodes .hqx and decodes .hex, .hcx & .hqx
.BinHex 5.0 encodes MacBinary and decodes .hex, .hcx, .hqx & MacBinary

        (b) "uuencode" is a binary to text translator that serves the
        same purpose as BinHex, except that it knows nothing about the
        Macintosh resource/data fork structure. uuencode was designed to
        allow UNIX binary files to be easily transferred through text-
        only interfaces, such as e-mail. Every uuencoded file contains
        a line similar to:
        
                begin 644 usa-map.gif
                
        followed by a series of lines of ASCII text characters (which
        are normally 60 characters long and begin with the letter 'M'). 
        The file ends with a line containing the word 'end'. There may 
        be other special keywords included.  Usually, one won't find 
        Macintosh files in uuencode format; however, most non-Macintosh 
        specific binary data posted to Usenet is uuencoded, so if you 
        wish to use any of this data (such as the images posted in 
        alt.binaries.* and elsewhere), you will need to deal with 
        uuencode. The programs 'uuencode' and 'uudecode' exist on most 
        UNIX systems. If not, ask a local expert to find them. Several 
        programs allow you to convert to and from uuencode using your 
        Macintosh; among these are UUTool 2.3.2 and UULite 1.7. 
        uencoded files are usually denoted by the suffix ".uu".

        There is a StuffIt translator to handle uuencode conversion.
.StuffIt Expander 3.5.2 with DropStuff and Expander
.Enhancer 3.5.2 will also decode a uuencoded file.

.uuUndo, distributed with John Norstad's NewsWatch 2.0b13,
.will also decode a uuencoded file.
        
        (c) atob and btoa are programs typically found on UNIX systems
        that also convert between binary and ASCII-printable character
        sets. Although not as popular as uuencode, btoa produces smaller
        text-compatible versions of binary files that can be e-mailed or
        posted on Usenet. Check your local man pages for details.
        
        There are StuffIt translators to handle atob/btoa conversion.

        
[2.4] What is Apple-Single/Double ?
-----------------------------------
        
        AppleDouble is another means of storing Macintosh files on
        non-Macintosh computers or filesystems, particularly on UNIX
        filesystems that also allow files to be mounted under the
        Macintosh operating system via AppleShare (or an equivalent
        product).

        AppleDouble files are actually two files. The data fork
        of the corresponding Macintosh file is stored in a single
        file just as it exists on the Macintosh using the original
        filename. The resource fork is stored in a second file whose
        name is obtained by prefixing the original filename with '%'.
        More extensive documentation is available at 
.ftp.support.apple.com.
        
        A few Macintosh programs decode these files; one such utility
        is Tiger 1.11. The macutils UNIX utilities [see 6.5] may also
        be useful. Eudora 1.4 and later also handles this format.
        
        If you are trying to figure out how to access the files in
        the 'mac.bin' directory at ftp-archive maintained by the
        University of Michigan, don't bother; all those files exist
        in .hqx format in the 'mac' directory.

        
[2.5] What do file suffixes like .hqx, .sit, .bin, etc ... mean and how
-----------------------------------------------------------------------
        can I convert such files back to normal Macintosh applications
        and documents?
        
        Most files available by FTP or posted to Usenet are modified
        twice to allow them to more easily pass through foreign computer
        systems. Files may be compressed to make them smaller, and/or
        they are almost always translated to either BinHex (.hqx) or
        MacBinary (.bin) format (see [2.2] and [2.3] for an explanation
        of these formats).
        
        How a Macintosh file has been translated and compressed for
        transmission is indicated by its suffix.  Normally a file will
        have a name similar in form to: filename.xxx.yyy, where:
        
                .xxx indicates how it was compressed
                .yyy indicates how it was translated
        
        Usually, .xxx is one of: .cpt, .dd, .sea, .sit
        Usually, .yyy is one of: .bin, .hqx, .image
        
        To convert a file back to its native Macintosh format, you will
        typically need to go through one step per suffix. For example,
        the filename "Swatch.cpt.hqx" indicates that a Compact Pro
        archive (.cpt) "Swatch" has been translated to BinHex (.hqx).
        To recreate the file(s) in the original archive, you must
        first 'undo' the BinHex transformation, creating a Compact Pro
        archive, and then open the Compact Pro archive and extract
        the file(s) in the archive.

        You can use the following table to determine what Macintosh
        programs decode which formats. For a more complete description
        of the various Macintosh archival programs, see the excellent
        FAQ for comp.sys.mac.apps.

.(This table was contributed by Bruce Grubb <bgrubb@scf.nmsu.edu>.
.Regular updates of this list can be found at sumex or any of its
.mirror sites, in the /info-mac/comm/info directory. The filename
.is of the form mac-ftp-list[version #].hqx. You can find the format
.chart by itself, in the same places, as format-chart-[version #].txt.)

.Programs for the Macintosh
.--------------------------

                                                             unix  gzip  .uu/
.Macintosh         .cpt .sit .hqx .bin .zip .arc .tar  .Z  .gz/.z .uue
.Stuffit Expander*   D    D    D    D
. w/ DSEE*           D    X    X    X    D    D         D     D     D
.StuffIt Lite**      D    X    X    X    {see note below}
.StuffIt Deluxe**    D    X    X    X    D    D    X    X     D     X
.SITcomm             D    X    X    X    D    D    X    X           X
.ArcMac                                       X
.BinHex 4.0                    X
.BinHex 5.0                    D    X
.Compact Pro 1.5.1   X   D/N   X
.Extractor 1.2.1     D   D/N   D
.HQXer 1.1                     X
.MacCompress                                            X
.MacGzip                                                D     X
.ShrinkWrap 1.3.2*^  D    D    D    D    D    D         D     D     D
.SunTar 2.0.4                  X    X              X                D
.Tar 4.0b                                          X
.UnZip                                   D
.UU Lite                                                            X
.uucd 2.3                                                           X
.UUTool                                                             X
.uuUndo                                                             D
.ZipIt 1.3.2b1                 D    D    X

.Programs for other computers
.----------------------------
.
.Other                                                unix  gzip  .uu/
.computers         .cpt .sit .hqx .bin .zip .arc .tar  .Z  .gz/.z .uue
.extrac.exe          D
.macutil (unix)
. hexbin                       D                                    D
. macunpack          D   D/U                            D           D
.mcvert (unix)                 X    X
.PKZIP                                   X
.unsitins.exe             D


.N = Cannot decode .sit dlx {Type SITD} files
.D = Decode only
.X = Encode and decode
.U = Uncertain or Unknown

..sit refers to both 1.5 and dlx. Otherwise a '/' is used {1.5/dlx}.
.Note: Almost every Mac communications program can decode .bin files.

.*   DropStuff with Expander Enhancer is an $30 shareware addon for 
.    Stuffit Expander.  DSEE is also used by other programs {marked with a *^}
.    to expand files.  Current versions are 3.5.2 as of this writing.
.**  Stuffit Deluxe translators can be used with Stuffit Lite.  Current
.    versions are 3.5.0 as of this writing.

                                Table 2.5.1


.Special note: .hqx, .txt, and .uu files are the ONLY files that can be
.downloaded in ASCII mode; all others must be downloaded in BINARY mode for
.the file to decompress properly.  Otherwise you will get errors such as
."unreadable file" or "file is corrupt" when you try to decompress them. 

        Note also: StuffIt Deluxe now includes translators for .tar, .uu,
        MacBinary, atob, btoa, AppleLink packages, AppleSingle, DiskDoubler,
        and UNIX compress. These translators can also be used with StuffIt
        Lite. .arc and .zip translators are also distributed with StuffIt
        Deluxe, but remain part of the commercial package. 

.StuffIt Deluxe and StuffIt Lite 3.5.0 no longer support DiskDoubler
.files. (1/95)

        The following file suffixes indicate formats that are native
        to the Macintosh and which can be manipulated using the indicated
        programs:
        
        .bin    MacBinary files; see [2.2]
        .cpt    Compact Pro archive files; [see 3.6]
        .dd     DiskDoubler archive files; [see 3.6]; DDExpand, DiskDoubler
        .hqx    BinHex files; see [2.3], [3.7]
        .image  Apple DiskCopy disk image file (typically used for
                distributing system software); latest version available
                via anonymous ftp from ftp.support.apple.com; can also be
.."mounted" as regular volumes with MountImage and ShrinkWrap
        .pit    Packit files; [see 3.6]; an old compression format
..which has been replaced by .sit. In general, a program
..that handles .sit files can decode .pit files as well.
        .pkg    AppleLink package files, replaced by .sit. StuffIt to decode.
        .sea    Self-extracting archive files; this usually denotes an
                application which can be double-clicked upon to create
                a decompressed version of the archive, without the need
..for any decoding program
        .sit    StuffIt archive files; [see 3.6]
        .sitd   mistakenly used to indicate files created by StuffIt
                Deluxe; *all* StuffIt files should be given the .sit
                extension (says the author!)

                                Table 2.5.2

        
        The following file suffixes indicate formats that are not native
        to the Macintosh, but in most cases, files of these types can
        be manipulated on the Macintosh using the indicated programs.
        
        .arc    MS-DOS PC archive file; ArcPop, MacArc, SE+DS+EE
        .arj    MS-DOS PC archive file (more common in Europe than U.S.); 
..unArjMac, DeArjl
        .gif    Compuserve Graphics Interchange File; many programs,
                free, shareware and commercial exist to display and/or
                modify these images; some of the popular shareware ones
                are: QuickGIF and GIFConverter.
..lha.Amiga or old MS-DOS PC archive file; MacLHa
        .lzh    Amiga or old MS-DOS PC archive file; LHarc, MacLHa, Macunpack
        .shar   UNIX shell archive file; Unshar 1.5
        .uu     UNIX uuencoded files; see [2.3]
        .Z      UNIX 'compress' archive file; MacCompress 3.2, SE+DS+EE
        .gz     GNU ZIP file; typically created on UNIX; MacGzip, SE+DS+EE
..z .Early suffix for GNU ZIP files.  Due to confusion with the UNIX 
..'compress' suffix {.Z} it was abandoned in favor of the .gz suffix.
        .zip    MS-DOS PC archive file; UnZip, ZipPop, ZipIt, SE+DS+EE
..taz.A common abbreviation for .tar.Z
..tgz.A common abbreviation for .tar.gz
..txt.ASCII text file
..zoo - old {~1989} PC/Amiga format, replaced by .arc; MacZoo, MacBooz
.. to decompress


        ! "SE+DS+EE" means StuffIt Expander 3.5.2 with DropStuff and Expander
.  Enhancer 3.5.2 (StuffIt Expander is free, and DropStuff with
.  Expander Enhancer is a $30 shareware product).

.Note: .gz and .Z compression systems, while both native to UNIX, are
.completely different, and these suffixed may not be interchanged.

                                Table 2.5.3

[2.6] How can I use a binary-downloaded file that appears as an
      unusable text file on the Mac desktop?
-----------------------------------------------------------------------------

Celeste Dolan    <celeste.dolan@ledge.com> responds:

A familiar problem, and one I've seldom been able to solve by changing
the file type and creator of the "text file." The -39 is a "logical end
of file" error, for what that may be worth.

I know of two methods that will restore the PC-downloaded file to a file
that your Mac will recognize. Method #1 requires Apple File Exchange,
which comes with your System Software set on the "Tidbits" disk. It also
requires the Mac-to-MacBinary/MacBinary-to-Mac set of translators for
AFE, which do NOT come with AFE on the System set. I found them on AOL a
couple of years ago, but they are probably available at some of the
usual ftp sites. Put the translators in the same folder as AFE and open
AFE. Make sure BOTH drive windows are active and choose "MacBinary to
Mac" from the menu called either "Mac to Mac" (if you don't have a DOS
disk in your floppy drive or you're running something like PC File
Exchange that lets you access DOS disks from the desktop) or "PC to Mac"
(DOS disk in floppy drive and no DOS-mounting software running).
Highlight the file that needs fixing and hit the "translate" button in
the center of the screen. The translated file will have its proper Mac
icon and behave the way you expect it to.

Method #2 uses StuffIt. I have tested this with StuffIt Deluxe 3.0.7,
but not with StuffIt Lite 3.0.7 (shareware version). Open StuffIt, and
make sure you have your preferences set to show the "Translate" menu. Go
to this menu and choose "MacBinary" from the translator list. A submenu
with the choices "encode" and "decode" will appear. Hold down the OPTION
KEY, choose "decode" and navigate to the file you want to fix. (In my
experience, the file may not show up in the window if you don't hold the
OPTION key down.) Tell StuffIt to open the file and then where to save
the decoded file. Save, and you'll have a usable file.

Patrick Hoepfner <hoepfner@haiti.gsfc.nasa.gov> adds:

Method #2 1/2. Drop the file onto StuffIt Expander.

