Electronic File Transfer & Conversionby Gabe Bokor
This article is an update of a file originally posted in FLEFO (CompuServe) Library 11.
Almost all professional translators currently work with either IBM
PC compatible (80%) or Macintosh (20%) computers. Since our
customers are increasingly requesting translations in electronic
form, the need arises to transfer word-processed files from one
platform to another and to convert them between the different
word-processor formats. New software and hardware have made file
transfer and conversion simpler and easier in the past few years,
and technological progress in the near future is expected to
continue in the same direction.
In order to successfully transfer and convert electronic files
between the Macintosh and DOS/Windows, some understanding of the
difference between the Mac and PC file structures is necessary.
PC files have a simple (binary) structure and can be stored on either
PCs or Macs without losing any of their characteristics. If a PC document is
transferred to a Mac, e.g. via modem, diskette, or network, the Mac
will recognize its filename, creation date, and size without
difficulty. In general, it will not recognize the program in which
the document was created, but will show a generic icon or the icon of the
application used for transferring the file. For the
Mac, all PC documents, and even applications, look like a text
only document and can usually be opened in a word processor,
although what appears on the screen may be gibberish.
Mac files have a more complex, double-fork or Mac-binary, structure. Each Mac
file (except text only files) has a data fork and a resource fork. Most of the bytes in word processed or other
documents can be found in the data fork of the file. The
resource fork contains special instructions for the creator
application or the computers operating system. Documents (but not applications) may have a zero-length resource fork.
Mac files have two special four-letter codes in a special location
of their data forks. One identifies the file type and the other the
creating application. These identifiers establish a link between the document and the
application, which allows the resources in the corresponding application (if installed)
to show the file with the icon corresponding to that
specific file type. They also cause the corresponding application to
load when you double click on the icon of the document.
Applications have relatively large resource forks. Unlike documents,
applications written for one platform do not work and cannot be
easily converted to work on the other platform.
PCs cannot store double-fork Mac files. If a Mac file is copied to
a PC via a network or a Mac-disk-reading utility, the resource fork
is either lost or copied over as an invisible second file. If the
file is copied back to the Mac, the resource fork is generally not transferred,
in which case the Mac can no longer recognize the file as a Mac document created by a
specific application or as an application.
PC-Mac file transfer
PC files can be transferred to the Macintosh via modem, diskette,
For modem transfer, a transfer protocol such as ZModem, YModem,
Kermit or XModem (listed in decreasing order of efficiency) must be
used for all but text-only files. It is advisable, although not necessary, that the MacBinary
option on the Mac be disabled. Some Mac communication software
automatically selects a MacBinary or Binary transfer protocol
depending on whether a Mac or a PC (or text) file is to be
transferred. CompuServe has a proprietary transfer protocol,
CompuServe B+, which is selected by default by almost all CompuServe-specific software.
Macs equipped with the superdrive for reading high-density diskettes and
the PC Exchange Control Panel software installed can read PC diskettes
directly. The files can be read and processed directly from the PC
diskette or copied over to the Macs hard disk for faster
processing. PCs can read removable Syquest, ZIP, or
Bernoulli cartridges formatted for the Mac with special software such as Executor by Ardi or Mac-In-DOS by Pacific Micro. With the appropriate software, such as HDT ToolKit by FWB Software, Macs can read
PC-formatted ZIP drives by IOmega; CD-ROMs can usually be read by both Macs and PCs. The same drive can always be
used for reading and writing either PC- or Mac-formatted cartridges.
Mixed PC-Mac network software such as Novell, Timbuktu (by
Farallon), or MacLan by (Miramar Systems) can transfer PC files to Macs over a LocalTalk or Ethernet physical network.
When a PC file is transferred to a Mac via a PC disk read by the PC Exchange
Control Panel or via network using special network software, it receives the filetype
and creator codes of this software, and it will appear with the icon
corresponding to this software.
Mac-PC file transfer
As mentioned before, Mac files normally have a Mac-binary, or double-fork
structure that the PC cannot handle directly. Therefore, it is
convenient to convert any Mac file prior to transferring it to a PC
or a PC-based network (or to another Mac via a PC or an on-line
service) so that its structure will resemble the binary structure of the
conventional PC file. The Mac software to accomplish this is called
MacBinary (formerly BinHex), and it is available as freeware from
CompuServe (GO MACFF, filename BINHEX.HEX). It is also one of the
utilities of Stuffit by Aladdin Systems, v. 3.07 or higher, and
comes bundled with some communication programs. MacBinary adds a
header consisting of a few (usually 128) bytes to the file. This
header contains the file type and creator information and a
filename that can be different from the original Mac filename. It
acts as a wrapper, hiding the double-fork Mac structure for
transfer to and storage in a PC system.
When the file is transferred via modem, the MacBinary file transfer
protocol (ZModem MacBinary, YModem MacBinary, etc.) automatically
creates the binary PC header for the transfer. However, when the
transfer is done via diskette or a typical network (or when a Binary, rather
than a MacBinary, modem transfer protocol is used), the conversion
from MacBinary to Binary format must be done prior to the transfer in a separate
If a Mac file is converted to a PC format, e.g. WordPerfect DOS or
Microsoft Word Windows, on the Mac and subsequently transferred to a
PC, no MacBinary conversion is needed, since the converted file no
longer has the double-fork structure of the Mac. Also text-only files
(which have no resource fork) need no MacBinary conversion prior to
their transfer to the PC, unless they contain non-ASCII characters (accented and other non-English characters, special symbols, etc.).
If a Mac file (MacBinaried as described above) is transferred
back from a PC to a Mac, the reverse Binary-MacBinary conversion is
needed to strip away the binary wrapper and expose the original
double-fork Mac structure. This conversion is automatic when using
modem transfer with a MacBinary protocol on the Mac side, or manual
when transferring via diskette or network.
Note about Text Files: Plain 7-bit ASCII texts without special
(non-English or graphic) characters use the same character set on
the Mac and the PC, except for the carriage return character, which
is one character on the Mac (ASCII # 13), but two characters on the
PC (# 13 and Line Feed ASCII # 10). Therefore a text originally
created on a PC may show an extra character after each forced line
break on the Mac, while a Mac text may not wrap around properly in
some PC editors. The extra character can be added or removed on the
Mac by searching (in Microsoft Word) for ^13 and replacing it with
^13 ^10 or vice-versa. 8-bit text files (such as texts with
accented or other special characters) use different characters for
the Mac, DOS, and Windows above ASCII # 128, and a conversion
utility is needed for the proper characters to show in each
File transfer via on-line services and the Internet
CompuServes Mail system accepts both plain text and binary (word
processed, DTP, graphic, etc.) files to be sent from one CompuServe account to
another. For binary transfers, a file transfer protocol is
needed, and, when transferring a Mac file from a Mac, a MacBinary
protocol must be selected or the file must be converted from
MacBinary to Binary prior to the transfer. Most CompuServe-specific
software automatically selects the CompuServe B+ protocol. CompuServe Mail (OLDMAIL) also supports XModem (dont use it if you can avoid it), and Kermit
(slow but reliable). It does not support ZModem.
Some other on-line services only accept plain text files as e-mail. Internet e-mail is
also basically restricted to 7-bit plain text files (no accents or special
characters), but fortunately any file can be converted to (7-bit) text for
transfer as e-mail. This conversion is accomplished by most popular Internet
mailers (Eudora, Netscape and others) using automatic client-side MIME encoding/decoding of 8-bit files
sent either in the body of the message or as attachments. Recently, CompuServe has also introduced automatic host-side MIME encoding/decoding which, contrary to the Internet, is accomplished not by the users software, but by the CompuServe host. This new
capability allows easy transfer of binary files between CompuServe and other on-line services, such as AOL, or the Internet without need for manual asciicizing via UUENCODE, MIME, BinHex, or RTF.
The markup language of the World-Wide Web, HTML, provides both
conversion to plain text and indirect Mac <--> PC
conversion, inasmuch as properly encoded web pages can be read correctly on
either platform. You should have no difficulty in reading words like Überschuß or animação, or the curly
quotation marks and apostrophes in this text regardless of
what platform you are using.
Conversion to plain text, when needed, should always be the last operation prior
to file transfer if the file is also subjected to some other
operation ( e.g. file conversion and/or compression). Conversion from plain text to
Binary or MacBinary should be the first operation after the file is received.
FTP file transfer of binary files to or from an FTP server on the
Internet is also accomplished with user-transparent asciicizing/de-asciicizing. Mac files are usually stored in the BinHex format on the server and converted to MacBinary by the FTP client software.
Word processing format conversion
Since translators usually deal with word-processed texts, we shall
only discuss inter-platform conversion of word-processed files.
Almost any Mac <--> PC conversion is done more efficiently on the
Mac because of the Macs capability of handling either single-fork
or double-fork file structures.
Recent versions of most major word processing programs (and
also some DTP, spreadsheet, and other programs) on both the Mac and
the PC can read their counterparts from the other platform. They
also come with some built-in conversion utilities. Microsoft Word
for the Mac (v. 5.1) can save files in RTF, RFT-DCA, Word for DOS
5.5, Word for Windows 1.0 and 2.0, Word Perfect 5.0 and 5.1, and
Microsoft Works. It can also read files of the same formats plus
(with the add-on Word for Windows 6.0 Word for DOS 6.0 Converter)
also Word 6.0 for Windows or DOS. This latter utility is available
in the Microsoft File Finder forum on CompuServe (GO MSFF, filename
MSWRD6.SEA), and it should be placed in the Word Commands folder to
work properly. Word 6.0 (Mac) has the same file format as its
Windows and DOS counterpartsthe software adds the missing
resource fork when the PC file is opened from Word 6.0 (Mac).
Microsoft Word 6.0, which can freely interchange files between the Mac and
Windows, can also save files in RTF and
Word/Mac 4.0-5.1 formats. WordPerfect 5.2 Windows (but not WP 5.1
DOS) is supposed to read and write RTF, although I never succeeded
in having my copy of the software do either.
An excellent standalone file conversion software package is sold by DataViz:
MacLink Plus (for the Mac, latest v. 9.0) and Conversions Plus (for Windows, latest v. 3.53) DataViz Inc., 55 Corporate Drive, Trumbull, CT 06611, 800-733-0030 or 203-268-0030, fax: 203-268-4345).
This software includes a large number of PC <--> Mac conversion utilities, as well as conversion into and from RTF and some graphic, spreadsheet,
and database formats. It converts word-processed files not only in the major West-European languages, but also in some Eastern European languages and languages using non-Latin alphabets such as Cyrillic, Greek, and Arabic, provided the appropriate fonts are used on both platforms.
When a PC file is converted to a Mac format on the PC, its resource
fork is created on the Mac (after the file is transferred) either by the Mac
application itself or by a specific utility. One of these utilities, Stamper, was
supplied with the Windows version of Word for Word (now discontinued). It
also adds the file type and creator codes corresponding to the Mac
application (e.g. WDBN/MSWD for Microsoft Word).
Other file type/creator changers and resource editors are available
in the Mac forums of CompuServe and at different Internet sites. Some
of these utilities, however, require that you know the file
type/creator codes of the application format into which the file was
Acknowledgments: Thanks to Alicia Gordon, Los Angeles, CA and Nigel Palmer, Paris, France for
their valuable contributions to this article. Further additions/corrections are gratefully accepted and will
be incorporated in future editions of this article.
© Copyright 1997 Gabe Bokor
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