Does the above phrase make your blood run cold? If so, you are not alone. With more and more people on-line, sending files to each other becomes a real expectation. If you need to do more than copy text from your word processor and paste it into your mail message, file size and format become major issues. The following is aimed at on-line file transfers but much of it applies equally to exchanging files by disk.
Sending a large file is slow. Under ideal conditions a 28.8 KBaud modem takes about 7 minutes to send a 1MB file. The Net seldom allows this speed — 14 minutes is more realistic. Usually attachments must be downloaded to the recipient before they can be erased. It is rude to send a large attachment without first getting the recipient’s okay. If you have problems with your computer hanging up before it finishes downloading or uploading a file, check with your e-mail service provider about “time outs”. It is often much easier for all involved to send floppies or a Zip cartridge Fed-Ex than for both you and the recipient to spend hours on-line sending a large file or many files. Newer Macs can read floppy disks and Zip cartridges from DOS and Windows machines but not vice versa without special software. The Mac owner needs to put their file onto a DOS (IBM formatted) floppy or Zip cartridge before sending it. Zip drives are becoming almost universal among folks who are exchanging large amounts of data: for $149 you have 100 MB of removable drive space, as low as $12 each for additional cartridges. Other media such as Jaz, Syquest, backup tapes and the like should not be sent without checking with the recipient. Syquest cartridges of the 44 and 88 MB variety are flaky enough that I wouldn’t send them through the mail.
Making a large file smaller: Utilities like PKZIP for DOS, WinZip for Windows (ZIP) or StuffIt (SIT) for the Mac can compress a large file, making it take less time to send. The recipient can download a trial copy of the uncompression utility (www.pkware.com, www.winzip.com, www.aladdinsys.com) or you can make a self-extracting version of the file. Unfortunately compression doesn’t work well cross-platform (Mac to Windows and vice versa). There is a Mac version of WinZip and a Windows version of UnStuffIt but I have not had good luck with either. Three file types, LZW-compressed TIF, GIF and JPEG, are already compressed and usually will not get smaller if attacked with a compression utility.
File Encoding: Because e-mail often goes through many computers and diverse operating systems, some types of files are trashed if they are not encoded. Your e-mail program will usually do this encoding automatically. MIME is the most frequently used encoding. If you get a MIME encoded attachment that gives an error of the “don’t know how to read this” type, try saving the file from the e-mail program. Be sure to give it a proper file name and extension if needed. The process of saving should automatically strip out the encoding if you are using a common e-mail program like Netscape mail, Internet Explorer mail, Eudora or Pine. Open a program which you know can read this type of file and then go to File, Open in the program and open the file. Bin Hex (HQX) is an older encoding sometimes used by Macs. StuffIt can usually read it directly. If not, you can try first opening the file in your word processor, deleting the readable part and saving the rest as text format with an HQX extension on the file name. Then open StuffIt and have it open the file.
FTP vs attachment: Sometimes you need to send a file by itself rather than as an attachment. For example, uploading your web page to your ISP (Internet Service Provider). FTP (File Transfer Protocol) is used for this. Ask the person to whom you are FPTing the file for instructions.
Once your file leaves your computer, will the intended recipient be able to read it? Ask if they have your program and version number. If not, you’ll need to save it in a format they can read. Look under “Save as” and change the file type or “Export” and pick the correct file type. If the file is going to an unknown machine, file names should be no longer than 8 letters or numbers, no spaces, followed by a period and the three letter extension which designates the file type. If you don’t know (or can’t find out) what file format they can read, use the following list of formats as your guide. If the format is referred to by more than three letters, the three letter extension to use is in parentheses.
Word processing (Word, Word Perfect, Works word processor etc.): save as Text or Standard ASCII (TXT) if you have no formatting such as indents, size changes, bolding or italics you need to retain. Almost any word processing program can read this. Save as Rich Text Format (RTF) if you do have formatting to retain but be aware that some older word processing programs can’t read this format. HTML (HTM) is becoming a standard because most people have browsers which read it. The common browsers, Netscape Navigator and Internet Explorer, can be downloaded for free (home.netscape.com, microsoft.com). Don’t use HTML if you need to send an exact copy: the formatting changes slightly and graphics may cause problems. If you want to send an exact copy which will print on their printer as close as possible to what you see on your screen, try Adobe Acrobat (PDF). You need to purchase Adobe Acrobat Distiller to do this but in some cases it is worth it. The IRS uses PDF for its forms on-line. Your recipient will not be able to change the file and must have Adobe Acrobat Reader but this can be downloaded for free (adobe.com).
Desktop publishing (PageMaker, Quark, Publisher): you must match their program and version to keep the structure intact. Otherwise you can export the text as for word processors and send the graphics separately. See also HTML and Acrobat under word processing above.
Bit-mapped graphics (scanned images, Photoshop, Paint etc.): For printing, TIF is the best choice unless you know it is going into Windows Paint, then choose Windows Bitmap (BMP). For Web graphics use GIF for line art and JPEG (JPG) for photos.
Vectored graphics (Corel Draw, Adobe Illustrator, Macromedia FreeHand): Encapsulated Postscript (EPS) is widely recognized on the Mac Platform but the Windows platform needs a Windows Metafile unless the recipient has a Postscript printer. If you send a bit-mapped format (see above), you lose the advantage of vector format: the file gets large and the image can’t be made larger without getting jagged.
CAD (AutoCAD and many other technical drawing programs): Drawing exchange format (DXF)
Relational database (FileMaker Pro, Access, Paradox, dBase, Fox Pro): Try dBase 3 (DBF) or export the desired data as flat file (see below). Some databases can be saved as “run time” versions so the recipient does not need additional software to use the database but cannot change the structure.
Spreadsheet, flat file database (Excel, Lotus, Quattro, Works): Tab separated (TXT or TAB) is the better choice for modern software or going to a Mac. Comma separated (CSV or WKS), often called Lotus format, is all that is recognized by older software.
Presentations (Powerpoint, Persuation): These can often be made into a self-running slide show — they can look at it but not change it. See your program’s documentation for instructions.
Still more questions? Give us a call (206-523-0872) and we’ll be glad to help.
copyright 1998 Karen Seymour
Back to Articles index Back to The Computer Workshop home page