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Uuencoding is a form of binary-to-text encoding that originated in the Unix program uuencode, for encoding binary data for transmission over the UUCP mail system. The name "uuencoding" is derived from "Unix-to-Unix encoding". Since UUCP converted characters between various computers' character sets, uuencode was used to convert data that should not be translated between character sets. By encoding such data into a character subset common to most character sets, the encoded form of such data files was unlikely to be "translated", thereby destroying the file. The program uudecode reverses the effect of uuencode, recreating the original binary file exactly. uuencode/decode became popular for sending binary files by e-mail and posting to usenet newsgroups, etc. It has now been largely replaced by MIME and yEnc. With MIME, files that might have been uuencoded are transferred with base64 encoding. ==Encoded format== A uuencoded file starts with a header line of the form: begin Each data line uses the format: The file ends with two lines: ` end The second to last line is also a character indicating the line length with the grave accent signifying zero bytes. As a complete file, the uuencoded output for a plain text file named cat.txt containing only the characters ''Cat'' would be begin 644 cat.txt #0V%T ` end The begin line is a standard uuencode header; the '#' indicates that its line encodes three characters; the last two lines appear at the end of all uuencoded files. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Uuencoding」の詳細全文を読む スポンサード リンク
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