The Online World by Odd De Presno

at high speed. When the transfer is done, you logoff from the remote center to "get back" to your mailbox computer's prompt line. Now, you can transfer the file to your personal computer using communications protocols like Kermit, XMODEM, ZMODEM or whatever else is available. Binary files transferred as text codes -------------------------------------- If you do not have access to FTP, you must use ordinary email for your binary transfers. Usually, email through the Internet can only contain legal character codes (ASCII characters between number 32 - 126). Most systems cannot transfer graphics or program files directly, since these files normally contain binary codes (which are outside this ASCII character range). The solution is to convert binary files to text codes using a utility program called UUENCODE. The encoded file can be sent by ordinary email, as in this example: From [email protected] Fri Aug 16 16:32:37 1991 Date: Fri, 16 Aug 1991 09:31:34 CDT To: [email protected] Subject: Part 1/1 SIMTEL20.INF PD: The file PD:SIMTEL20.INF has been uuencoded before being sent. After combining the 1 parts with the mail headers removed, you must run the file through a decode program. ------------ Part 1 of 1 ------------ begin 600 SIMTEL20.INF M6T9I;&4Z(%-)351%3#(P+DE.1B`@("`@("`@("`@("`@("`@("!,87-T(')E M=FES960Z($IU;F4@,C@L(#$Y.3%=#0H-"B`@(%M.;W1E.B!$=64@=&\@9&ES M:6P-"AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH: M&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH:&AH: 6&AH:&AH:&AH:&AH:&AH:&AH:&AH:&@(Z ` end -------- End of part 1 of 1 --------- When you receive a message with uuencoded text, download it to your personal computer's hard disk. Use an editor to cut out the codes and paste them to an empty work file. Using the example above, the first line in your work file should contain: begin 600 SIMTEL20.INF and the last line should contain end Now, use a utility program called UUDECODE to convert the file back to its binary form (or whatever). More information about uuencoding and uudecoding is given in the BINSTART file mentioned above (for MS-DOS computers). It has a detailed explanation, BASIC source code for making the program UUDECODE.COM, and a DEBUG script for those preferring that. Versions of UUDECODE are also available for other types of computers. Transfer of pictures -------------------- Denis Pchelkin in Protvino (Russia) is 11 years old, has two cats and one dog, and has contributed beautiful computer graphics art to the KIDLINK project (1992). The file ART019 in the KIDART catalog of the North Dakota center contains one of his creations. It is a UUENCODEd picture in GIF graphics format. You can retrieve Denis' creation by sending a GET command to [email protected] . Put the following command in the TEXT of your message: GET KIDART ART019 The LISTSERVer will return a message filled with strange uu-codes. We assume that you have already retrieved the BINSTART file, and that you have a version of the conversion program. Your next step is uudecoding: Read the message into an editor or a viewing program. Cut and paste the codes to a work file. Keep the original as backup. Use the UUDECODE.COM program to convert ART019 into a GIF formatted file. Now, view the picture with your favorite graphics program. (Or use shareware GIF-viewers like PICEM, VUIMG, and VPIC for MS-DOS computers. These programs are available from CompuServe's IBM forums and other services.) Sending binary files in uuencoded form has weaknesses. One is the lack of automatic error correction when sending/receiving e- mail. Noise on the line can easily distort the picture. File size is another problem. UUENCODEing typically increases file sizes by almost one third. Some mailbox systems restrict the length of individual messages that you can receive, and the file may just be too big. If the uuencoded file gets too big, some services can (or will by default) split it up in parts and then sent separately. Tons of uuencoded public domain and shareware programs are available for retrieval by ordinary email. FTP by email ------------- While some services accept commands like GET KIDART ART019 by email, this is not so with the many so-called FTP libraries. Many of them can only be accessed by FTP. Services exist that will do FTP transfers by email for those not having access to the FTP command. The most popular is at DEC Corporate Research in the U.S. For more information, write a message to one of the following addresses: [email protected] [email protected] In the TEXT of your message, put the word "HELP". FTPMAIL lets you uuencode binary files for transfers. It can split large files up into several messages, thus helping you around local restrictions on the size of each incoming mail message.