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From: Bruce Grubb <
[email protected]>
Newsgroups: comp.sys.mac.comm,comp.answers,news.answers
Subject: comp.sys.mac.comm FAQ (2.2.5) 1/3
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From:
[email protected] (Bruce Grubb)
Last-modified: Dec 1, 2000
This is the comp.sys.mac.comm Frequently Asked Questions (FAQ) list
=====================================================================
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, comp.answers, and news.answers. Latest
versions of the FAQ can be retrieved via anonymous FTP from any
info-mac mirror and from
<
http://members.aol.com/BruceG6069/csm-comm-FAQ.txt>
This FAQ is purely a volunteer effort. Although every effort has been
made to insure that answers are as complete and accurate as possible,
NO GUARANTEE IS IMPLIED OR INTENDED. The editor and contributors have
developed this FAQ as a service to Usenet. We hope you find it useful.
It has been formatted in both HTMl and ASCII format for your browsing
convenience.
The editor/maintainer of this FAQ takes no responsibility for its
contents. Thanks to David Oppenheimer for giving me permission to
continue the FAQ.
Please send your corrections and comments to the editor, Bruce L
Grubb at
[email protected]
SHARE THIS INFORMATION FREELY AND IN GOOD FAITH.
DO NOT DISTRIBUTE MODIFIED VERSIONS OF THIS FAQ.
DO NOT REMOVE THIS NOTICE OR THE TEXT ABOVE.
(INCLUDING THE 'LastModified' HEADER; THANKS.)
Exception to the above: Excerpts of this FAQ not exceeding 9000
characters in length may be reprinted PROVIDED that
"the comp.sys.mac.comm Usenet newsgroup FAQ" is credited as the
source of the information. Even in this case, no editing of the
quoted material is permitted
=====================================================================
TABLE OF CONTENTS:
+ = Updated or New information
[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?
[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 encoding?
[2.3] What is BinHex? What is uuencode? What is Base64?
[2.4] What are AppleSingle and AppleDouble? What is MacBinary?
[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] After decoding and expanding a file I get an unknown document
file. How do I open this file?
[3] Macintosh File Transfers
[3.1] What is the difference between a commmunication and an
Internet connection?
[3.2] What commmunications programs are available?
[3.3] What Internet programs are available?
[3.4] What is Telnet, and what MacOS Telnet Programs are there?
[3.5] What's the best compression program to use when uploading
files to an archive or BBS? Are there any other guidelines
I should follow?
[3.6] How can I transfer Macintosh files to/from my Macintosh and
other non-Macintosh computers (eg: mainframes, UNIX boxes,
PCs)?
[3.7] Is there a newsgroup for MacOS binaries?
[4] Networking basics
[4.1] What is the difference between AppleTalk, LocalTalk,
Ethernet, EtherTalk, TCP/IP, etc?
[4.2] What is Open Transport?
[4.3] 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?
[4.4] How can I use the services of my EtherTalk network and print
to my LocalTalk-only printer at the same time?
[5] Internet Networking
[5.1] What kind of hardware and software do I need to have a
direct connection (ie use TCP/IP protocol) to the Internet?
[5.2] What are SLIP, CSLIP and PPP?
[5.3] FreePPP and OT/PPP (Remote Access) Frequently Asked Questions
[5.4] Do I have to know anything about Unix to use the Internet?
[5.5] Is there a UNIX program that will convert between BinHex
and MacBinary?
[6] Miscellaneous
[6.1] I just downloaded an .AVI file but Quicktime will not play it
correctly. Am I missing something?
Appendices:
[A] List of Common File Suffixes and Abbreviations
[B] Mac program archive list link and Vendor Information
[C] 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. Examples include internal Powerbook modems, ADB modems,
and internal NuBus modems.
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 hardware-handshaking cable
to connect it to your Macintosh. (see [1.2] for details).
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. The earliest models of the Macintosh used DB-9
(9 pin) connector, while from the Mac Plus to the first G3 macs
used mini DIN-8 (8 pin) connector for the two serial ports (modem
and printer), and the current G3 models use a USB port.
Finding a hardware handshaking cable for a DB-25 to DIN-8 14.4K+
configuration at most computer accessory store should not be very
difficult and typically sale $15.00 (10 ft) via mail order. Note
some older modem cables are -not- hardware-handshaking and can cause
such problems as repeated transmission errors, a drop in the transfer
rate, and possibly an aborted transmission.
I am not currently aware of any USB to DB-25 cables but given the large
number of DB-25 modems out there I imagine there either are some or soon
will be.
[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 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 : 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.
X2/K56flex : Two incompatable proprietary formats for 56K
Dependent on a digital equipment which some areas
do not have.
V.90 : standard for 56K modems
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 could the Macintosh serial ports really go?
--------------------------------------------------------
Orignally the MacOS supported up to an asynchronous data rate
of 57600 bps though the serial hardware could support much higher
transfer rates externally clocked (as much as 16 times synchronously).
The AV and Powermac introduced a different SCC clock and DMA based
serial driver which allowed 115,200 and 230,400 bps.
(Ward McFarland <
[email protected]>,
Dan Schwarz <Dan_Schwarz/
[email protected]>) USB which replaced
the serial ports can go as fast as 1.5 MB/s
While the ability of the serial ports to achive these speeds was
useful in the days of communications software (see [3.1]) its
importance dwindled with the introduction of Intenet communications
and PPP (see [5.3]). The reason is that many non-text files on the
Internet are already compressed which renders the built in MNP5 and
V.42bis compression methods virturally useless. In addition due to
limiations in equipment and phone line quality even a 56K modem
rarely gets a sustained throughput over 50K.
For these reasons the modem scripts that come with Open Transport
have 57600 bps as the maximum serial speed for a modem.
[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 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,
not only did Mac archive formats have to support them but a means to
turn the two fork Mac file into a data fork had to be developed so that
mac files could pass through non-macintosh machines (such as UNIX boxes,
or MS-DOS machines) without being damaged.
This also means that without modification non-mac archives and encoding
formats cannot be used to send mac files.
[2.2] What is encoding?
------------------------
To understand 'encoding' as the term is normally used on the Internet
one needs to understand the difference between "binary" and ASCII.
With the noted exception of text files computers store information in
"binary" format which means that all 8-bits of a byte are used. By
contrast ASCII originally only defined the first 7 bits of a byte
setting the high bit in each byte to zero. As an added complication
the character sets for byte values 128-255 used by ANSI and early
(1981-c1990) IBM PCs differed.
As a result for 8-bit information to reliably be sent between
computers it had to be translated into 7-bit ASCII text or 'encoded'.
This was especially true of Usenet and e-mail which even today mostly
supports 7-bit ASCII. Because 8-bits worth of data are being put into
a 7-bit text file encoded files are always larger than their binary
counterparts.
Due to its data and resource fork structure the Mac has an additional
type of encoding structure: Binary encoding. Unlike ASCII encoding
there is virturally no increase in file size but since these formats
are 8-bit they cannot be used on their own in the remaining areas of
the Internet that only support 7-bit (like E-mail and Usenet).
[2.3] (a) What is BinHex? (b) What is uuencode? (c) What is Base64 ?
---------------------------------------------------------------------
These are all ASCII encoding (see [2.2]) formats.
(a) 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). Since the
format is mainly used on already compressed files the RLE compression
method that can be part of the format is rarely used.
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.
Binhex 4.0 files also can be identified externally by the suffix ".hqx".
There is in fact a program called "BinHex 4.0" in various archives,
but it has a bug wherein it refuses to decode .hqx files with very
long names and 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 like
StuffIt Expander and other StuffIt programs, SunTar, and HQXer to
name only a few. StuffIt Expander has the advantage of also being
able to automatically expand StuffIt, Compact Pro, and Applelink
archives and being available on PCs.
UNIX utilities (see [5.6]) that manipulate BinHex, MacBinary II, and
other types of Macintosh files are also available though they are very
old.
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"; but it is NOT a
more advanced version of "BinHex 4.0" but rather a separate _binary_
encoding format (see [2.2]). BinHex 5.0, written by Yves Lempereur,
in 1985 was the first MacBinary converter available. BinHex 5.0 (also
called MacBinary I) was replaced by the MacBinary II format which
added support for several then new MacOS features (see [2.4b]).
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 I and decodes .hex, .hcx,
.hqx & MacBinary I
(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. Externally uuencode files are
usially denoted with the suffix ".uu" or ".uue".
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, don't worry as there are many programs allow you to
convert to and from uuencode using your Macintosh (see [2.6]).
(c) Base64 is the encoding format used by Multipurpose Internet Mail
Extension (Mime) files. The reason mime uses Base64 rather than the
more popular uuencode format is that uuencode is not really a standard
but rather a collection of related but different formats. This rendered
uuencode impractical as a cross platform encoding format.
Mac files being sent via e-mail are usially binary encoded (usially
in AppleDouble) before being encoded in Base64.
[2.4] a) What are AppleSingle and AppleDouble? b) What is MacBinary?
------------------------
These are all Mac binary encoding (see [2.2]) formats.
a) AppleSingle and AppleDouble were developed out of a need to share
Mac file between the MacOS and A/UX (Apple's first UnixOS) as well
as allowing A/UX users to edit MacOS files. The specs of these
formats can be found at
<
http://www.cis.ohio-state.edu/htbin/rfc/rfc1740.html>.
AppleDouble is useful today because it divides a Mac file into
two files: one for the data fork (with original filename) and the
other for resource fork (with '%' prefixing the original filename)
This made it easy to adopt AppleDouble to MIME - have non-mac
systems simply ignore the '%' file.
Mac e-mail programs that use AppleSingle and AppleDouble encode them
into Base64.
b) MacBinary is the Mac's standard binary encoding (see [2.2]) format.
MacBinary's purpose is to encapsulate *all* information (including
the filename, creation and modification dates, file type and creator)
contained in a Macintosh file for transport over a non-Macintosh medium.
Although a Macintosh program (called MacBinary) does exist
to do the converting to and from MacBinary, almost all modern
Macintosh telecommunications and Internet 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, and most other shareware and commercial 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."
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.
MacBinary III is an update to the vernerable c1987 format
that supports the icon badge custom routing information
finder flags that are part of MacOS 8.5.
Since then, BinHex and the MacBinary II have become the standard way
of encapsulating Macintosh files for transfer over foreign systems
throughout the Internet, USENET, and elsewhere. MacBinary is also
used as a way to retain Mac file information within non-mac archive
formats. For example MacLHA, ZipIt, and DropZip use MacBinary in this
manner for the PC formats .lhz and .zip respectively.
MacBinary's correct MIME type is "application/x-macbinary" and if
you want StuffIt Expander to launch when you double click on the file
set the type and creator fields to BINA and SITx.
[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.
First they are compressed and then either ASCII or Binary encoded with
BinHex (.hqx) and MacBinary (.bin) being the formats of choice for
Macintosh users (see [2.3] and [2.4] for an explanation of these
formats).
Generally the suffix on these files only tells you the encoding
method used and nothing about the compression method. As a result
StuffIt Expander has become the defacto decoder utility especially
when combined with the StuffIt Engine. You can use the following
table to determine what Macintosh programs handle which formats.
For a more complete description of the various Macintosh archival
programs, see the excellent FAQ for comp.sys.mac.apps.
This table is also part of the Mac-FTP-list and listed on its own as
format-chart.txt both of which are at
<
http://members.aol.com/BruceG6069/>
as well as being archived on any info-mac mirror site, in the
/info-mac/comm/ directory.
Here's a handy chart to keep track which programs unmangle which formats:
unix gzip .uu/ .b64/
Macintosh .sit .hqx .bin .zip .tar .Z .gz/.z .uue .mime*
Stuffit Expander** D D D D D D D D D
DropStuff** E E
DropZip** I E E
ShrinkWrap*^ D D D D D D D D D
StuffIt Deluxe*** X X X X X X D X D
Decoder 1.3.4 D D
MacCompress X
MacGzip D X
MPack 1.5.1 D D X
SunTar 2.2.2 X X X X D
Tar 4.0b X
uucd 2.5.0 X D
YA-Decoder D D D D
ZipIt 1.4.0 D D X
Other unix gzip .uu/ .b64/
computers .sit .hqx .bin .zip .tar .Z .gz/.z .uue .mime*
Aladdin Expander 5 D D D D D D
Aladdin DropStuff X X
Aladdin DropZip X X
binhex-pc-13 X
Expander (Linux) D D D D D D D D
macutil (unix)
hexbin D D
macunpack D/N D D D
mcvert (unix) X X
MPack D D X
PKZIP X
StuffIt (Win)*** X D D X X X X X
xferp110 (win) X X X
D = Decode/decompress only
E = Encode/compress only
N = Cannot decompress Deluxe .sit [Type SITD] files
I = MacBinary format is supported internally only
X = Encode and decode
sit refers to all versions of the Stuffit format. A '/' denotes the
inability to handle certain formats as outlined in the legend above.
hqx = BinHex4; .bin = BinHex5, MacBinary I, II, and III
* .b64/.mime (Base 64) refers to the encoding format used by the
Multipurpose Internet Mail Extension. For more information consult
the MIME FAQ.
<
http://www.cis.ohio-state.edu/hypertext/faq/usenet/mail/mime-faq/top.html>.
** Engine refers to the StuffIt Engine which is part of StuffIt Deluxe and
DropStuff with Expander Enhancer [a $30 shareware addon for Stuffit
Expander] Programs that can use the Stuffit Engine are marked with a *^.
Current public versions of the Expander and the Engine are 6.0.
*** Current version as of this writing is 6.0.0.
Aladdin has a more detailed format chart at their site
<
http://www.aladdinsys.com/faqs/fileformats.html>
Table 2.5.1
Note: .gz and .Z compression systems, while both native to UNIX, are
completely different, and these suffixes cannot not be interchanged.
WARNING: .hqx, .uu, .b64, and .txt files are the ONLY files that can
be downloaded in ASCII mode; all others must be downloaded in BINARY
[IMAGE] mode for the file to decompress properly. This is especially
true of ".bin" and "unstuffed" files. Otherwise you will get errors
like "unreadable file" or "file is corrupt" when you try to decompress
them.
Less commonly used formats. Those followed by a + are Mac formats.
arc
old (c1990) MS-DOS compresion format, replaced by .zip.
Decompressed by Stuffit Engine, StuffIt Deluxe,
MacArc (can also compress), and Aladdin Expander.
arj
PC format common to European sites. Decompressed by unArjMac,
DeArj, Aladdin Expander, and Stuffit 5.5 (Win).
cpt +
Mac compression format created by Compact programs (last
updated April 1995). Decompressed by Stuffit Expander,
StuffIt Deluxe, Compact Pro, and macunpack.
dd +
Disk Doubler {Mac} format. Decompressed by DDExpand, DiskDoubler
and Stuffit Expander 5.5.
exe
DOS/Windows executable file (program); also used to create
self-extracting archives. An .exe file used as a self-extracting
archive can usually be decompressed with Stuffit Expander w/ DSEE.
Use of this format of an archive is strongly discouraged as it
can cause problems crossplatform.
html (.htm)
WWW document. Used by WWW browsers such as Netscape and lynx.
image/.img/.ima/ (related format - .smi) +
These are all disk image extensions. They represent Mac disk image
(.image/.img), Microsoft Disk Image Utility (.img), and Winimage
(.ima) formats. Most can be mounted via StuffIt Expander 4.5/5.0
or ShrinkWrap 3.0
<
http://www.aladdinsys.com/developers/shrinkwrap/index.html>.
To eliminate the need for a mounter program there now exists a
self mounting disk image format called .smi. For a history of
Shrinkwrap consult the 2.1 site <
http://www.halcyon.com/shrinkwrap/>.
Note that .img is also used as an graphic file extension and
needs GraphicConverter to view.
lzh (related formats - .lha and .lzs)
old PC/Amiga format that is still quite popular in Japan and
by Aminet Amiga site <
http://us.aminet.net/~aminet>, largely
replaced by .arc and .zip elsewhere; decompressed via
Stuffit Expander 6.0, macunpack, LHA Expander 1.0.3, and
French KISS 2.2.0. StuffIt Deluxe 6.0 and MacLHA 2.2.1 also
can compress in this format.
pit +
old (c1989) Mac compression format created by PackIt programs,
replaced by .sit. Only StuffIt Deluxe expands this old format.
pkg +
AppleLink package format, replaced by .sit. Decompressed by all
present Mac StuffIt programs.
rar
A DOS compression format. Handled by MacRAR <
http://macrar.free.fr/>
and StuffIt Expander 6.0.
sea +
A special version of a Mac compression format that decompresses
itself when opened. The most common .sea files are Stuffit,
Compact Pro, and Disk Doubler. Use of this format is strongly
discouraged as it can cause problems crossplatform.
shar
Unix shell archive. Decoded by Unshar.
taz
another name for .tar.Z
tgz
another name for .tar.z and .tar.gz (do not confuse with .tar.Z).
txt (.abs, .doc)
ASCII text file. There is a slight differance between ASCII text
files of Mac, PCs, and UNIX systems which can cause problems when
trying to read them. Mac ASCII uses carrage returns, UNIX uses
line feeds, and PC uses both.
z
Suffix used by both Unix pack and early (c1993) Gzip files.
Due to confusion between these compression methods and Unix
'compress' suffix (.Z) it was abandoned in favor of
the .gz suffix. Unix pack itself has been effectively
replaced by both Unix compress and Gzip.
zoo
old (c1989) PC/Amiga format, replaced by .arc which in turn was
largely replaced by .zip. Decompressed by MacZoo and MacBooz.
Table 2.5.3
[2.6] After decoding and expanding a file I get an unknown document
file. How do I open this file?
---------------------------------------------------------------------
The best thing to do is to try and see if there is any way to figure out
what -broad- type of file it is: word processor, picture, sound, or movie.
Word processor
Tex-Edit Plus <
http://members.aol.com/tombb/index.html> will read
most of these out there though some will require Adobe Acrobat
Reader (.pdf) or a commerical word processor such as
MS Word or WordPerfect.
I should mention that Stuffit Expander has a little known
problem with PDF files; having the 'convert text files to
Macintosh file' option under cross platform on can mangle PDFs
to the point they are unreadable. This should -always- be
set to Never (I don't even understand why this option is
even there as any good word processor can do this for you).
Pictures
GraphicConverter (Shareware, $30-$35, /info-mac/gst/grf/,
http://www.lemkesoft.de/) is one of the most powerful shareware
graphic programs for the Mac. It is able to open about 100 graphic
formats, edit them, and save in about 40 of these formats including
.gif, .tiff, .png <
http://www.cdrom.com/pub/png/>, and .jpeg. But
even it cannot view propriety formats such as used by Photoshop or
Canvas or relatively obcure formats such as .ecc.
More details on graphic formats in general can be found in the
PC Webopaedia
<
http://webopedia.internet.com/TERM/g/graphics_file_format.html>.
Sound files
Sound App 2.6.1 (Freeware, /info-mac/gst/snd/) will play most sound
formats out there including .mod, mp3, .wav, .au, and .aiff.
Movie files
Varies depending on the movie file type. Quicktime 4.0 is able to view
.mov, .mpg (PPC Macs only), .fli/.flc, and .avi (1.0, 3.2) formats.
extensions for allowing QuickTime to handle the Indeo 3.2, 4.4 and 5.0
.avi formats can be accessed via Apple's QuickTime support page
<
http://www.info.apple.com/support/quicktime/> under the Update menu
or via Apple's QuickTime technologies page under "Indeo"
<
http://www.apple.com/quicktime/technologies/indeo/>
GraphicConverter is able to view .Ani, .dl, gif, and .fli/.flc formats.
Other files
Hopefully there is a document file that tells you what is needed
otherwise it is pretty much a lost cause.