acliu@skat.usc.edu (Alex C. Liu) (12/10/89)
In message <21658@usc.edu> I write: >Because of a system upgrade, the Mail Server here will go down for a >couple of days. Sorry for the inconvenience. Well, the system is just back up. (Not bad, down only for 2 days?) I have completely rewriten the server software so it will save some of my diskspace and added a couple of commands. Except for that, the changes should be totaly transparent to you. The most important change has been the ability to choose the method to encode binary files. Thus it will be compatible with machines that don't have Unix or UUencode. This new version (V2.0c) supports the old commands: path return-path send volume file help topic contents volume index volume receive volume file The "split" command has been disabled since the new version of the "send" command makes "split" obsolete, also, the never used "install" command has been eliminated. These commands work pretty much the same way as the ones in the previous version of the server, but all the known security bugs have been eliminated. Though some new features has been added to the "send" command. The commands are now case insensitive. (the file and volume names are NOT!) Also, two new commands have been added. maxsize integer This command is used to specify the max message size. Since some system will not deliver mail that is over certain size. This command will let you choose the maximum message size. Note, that this doesn't guarantee that the message will be bellow a certain size. Usually when splitting the file, the file is also shar'ed. So files increase size in around 2K. So you must account that when specifying the max message size. If you specify a zero value, the program will not bother checking the size of your message and send it asis (infinite message size.) The default maxsize is zero (infinity!) bencode [uuencode|btoa|hex] When the server detects that a message contains binary data it will automatically encode it using the method chosen with this command. (as a default, it will use uuencoding) This is because "mail" is a 7bit connection, and also some mailers might drop some characters along the way. This encoding (usually) guarantees a good file transmition. The syntax for this command is "bencode" followed by an argument word, which can be one of the follwoing: uuencode The file will be uuencoding before transmition. This is the standard Unix encoding algorithm (stolen from uuencode.c sources from uunet.uu.edu). The sources forthe uuencode/uudecode program(s) can be ftp'ed from uunet.uu.net or requested from this server (file unix-support uuencode) btoa This encoding algorithm first appeared with the USENET distribution of compress. My server uses the algorithm found in btoa V4.0 to do its encoding. It is more efficient than uuencoding, and also has some checksum numbers for error detection. hex This is an encoding method I made up. It basicly converts the binary data into Hex. And also it includes some checksums so I can feel more sophisticated :-). The main disadvantage is that the transmited information takes more than twice the time to send. The advantage, is that with some programming knowledge and some time you can easily decode the file. Retreive the file help binary.formats for more information on the file formats, and for a sample Commodore Basic decoding program, retreive the file help unhexf.bas (If you have any questions ASK!) The software for this new version of the server will be available as soon as I finish cleaning up my room! NOTICE: Due to my college studies, I can not possibly check what is stored in this archive. What ever you download from here, you do at your own risk. (If you want to volunteer to MODERATE this archive, please send me e-mail, I will greately appreciate any help in this) --- Alex C. Liu acliu%skat@usc.edu acliu@skat.usc.edu (Simple .signature, $CHEAP$)